A cost-plus construction contract in Florida obligates the property owner to reimburse the contractor’s actual, documented job costs and pay a separately negotiated fee for profit and overhead. That structure trades the certainty of a fixed price for transparency into every dollar spent, and it shifts the risk of cost overruns from the contractor to the owner. Whether that trade works in your favor depends almost entirely on how the contract defines reimbursable costs, how the fee is calculated, what audit rights you keep, and whether the document carries the lien-law disclosures Florida requires.
The Two Payment Streams
Cost-plus splits your payment obligation in two. The “cost” side covers approved project expenses the contractor incurs: materials, on-site labor, equipment, subcontractor invoices, permits, and inspection fees. The “plus” side is a separate amount for the contractor’s profit and general overhead. Because the contractor isn’t absorbing worst-case contingencies inside a lump-sum bid, there’s less incentive to pad. The flip side is that if lumber prices jump or the schedule stretches, you pay the difference.
That trade only pays off when you can see what’s being spent. A workable cost-plus agreement runs on open-book accounting, with the contractor sharing invoices, payroll records, equipment logs, and subcontractor agreements as the job moves. The contract needs to grant inspection rights throughout construction, not just at final payment.1Construction Dive. The Dotted Line: How to Prepare for a Construction Project Audit
What Counts as a Reimbursable Cost
The definition of reimbursable cost is the provision that will either protect you or drain you. Vague language is where disputes start. Spell out the categories of allowable expenses and, just as importantly, list what the contractor cannot bill back.
Costs typically reimbursed as direct project expenses:
- Materials at actual invoice price, net of any trade or volume discounts the contractor received.
- Wages, payroll taxes, and benefits for workers performing on-site construction tasks.
- Rental fees for third-party equipment, or, for contractor-owned equipment, an agreed internal rate reflecting depreciation, insurance, and maintenance.
- Payments to licensed subcontractors for specialized trade work.
- Building permits, inspection fees, and impact fees required by the local jurisdiction.
Costs you should exclude: the contractor’s home-office rent, administrative staff salaries, general business insurance covering the contractor’s whole operation, and any expense that benefits the contractor beyond your single project. The contract should also state whether the contractor may mark up material purchases or subcontractor invoices. A 5% handling markup on materials is common in Florida residential work, but it needs to be written in. If the agreement is silent and a 15% lumber markup shows up on an invoice, you’ll have a much harder time pushing back.
Equipment Rate Traps
Equipment billing is where cost-plus disputes get creative. Third-party crane rentals are straightforward; the invoice is the invoice. When the contractor charges for using equipment the company already owns, the rate is negotiable and sometimes billed at market rental prices that far exceed the actual cost of ownership. The contract should lock in either a published rate schedule or a formula tied to real ownership costs. External rental markets swing 15 to 20 percent seasonally and spike higher during construction booms, so fixing the methodology upfront protects both sides.
Reasonableness
Falling within a reimbursable category isn’t enough. The cost also has to be reasonable, meaning something a careful business owner would pay in a competitive market. If the contractor orders premium imported tile when a domestic option at half the price meets the specs, you can challenge it. Put the burden of justification on the contractor in the contract itself: any questioned cost has to be defended.
How the Contractor’s Fee Is Structured
The “plus” pays for profit and the overhead you’re not reimbursing as a direct cost. Three approaches show up most often on Florida projects.
Percentage of Cost
The fee is a fixed percentage of total reimbursable costs. Residential general contractors in Florida typically charge between 10 and 20 percent, adjusted for project size and the contractor’s volume. The obvious problem: every extra dollar of cost is an extra slice of profit. If you go this route, back it with strong audit rights and airtight cost definitions.
Fixed Fee
A flat dollar amount, agreed before work starts, that doesn’t move with the final cost. Agree on $75,000 and the contractor earns $75,000 whether the job runs on target or $50,000 over. There’s no incentive to inflate costs. This is the default most owners should push for when the contractor will accept it. The fee moves only through a formal change order that alters the scope.
Incentive Fee
A base fee plus a bonus or penalty tied to targets, usually completion date, total cost, or both. Finish under budget and the contractor keeps a share of the savings. Blow past it and the fee shrinks. It only works when both sides trust the cost-tracking system and the benchmarks are realistic.
Guaranteed Maximum Price
A Guaranteed Maximum Price, or GMP, caps your total obligation. Any costs above the ceiling come out of the contractor’s pocket, so you get cost-plus transparency without unlimited exposure.2AIA Contract Documents. Understanding Guaranteed Maximum Price Contracts If the project finishes under the GMP, the savings are typically split under a formula the parties set at the outset.
A GMP only holds when the scope stays put. Florida’s construction lien statute treats extras and change orders as part of the contract, with the price adjusting accordingly.3Online Sunshine. Florida Code 713.01 – Definitions Every scope change has to move through a written change order that adjusts the GMP by a documented amount. Without that discipline, the cap becomes a talking point rather than a limit.
Your Audit Rights
An audit clause is not optional in cost-plus. It’s your only real enforcement tool. The contract needs to address three things: scope, timing, and record retention.
On scope, the audit right should reach all reimbursable-cost documentation: invoices, payroll records, subcontractor agreements, equipment logs. Fixed-fee components and agreed unit rates aren’t audited at the cost basis, but you should still be able to verify quantities, hours, and units against those rates. A contractor billing 500 hours of crane time at an agreed rate still has to prove the crane was on site for 500 hours.
On timing, the contract should let you or a designated auditor inspect records during the project on reasonable notice, not only after final payment. A billing error caught in month three is far cheaper to fix than one discovered after close-out. A 24-hour notice requirement during business hours is standard.
On record retention, require the contractor to keep all project financial records for at least three years after final completion. Warranty issues sometimes surface long after the job ends and can reveal materials that were billed but never installed.
Florida Lien-Law Requirements Your Contract Must Handle
Florida’s Construction Lien Law, in Chapter 713 of the statutes, applies to every construction contract in the state regardless of pricing model. Ignoring these rules can leave you paying twice for the same work.
Notice of Commencement
Before any work begins, you must record a Notice of Commencement with the county clerk where the property sits and post a copy at the job site. No dollar threshold applies. The notice has to include the legal description of the property, the owner’s name and address, the contractor’s name and address, and information about any construction lender or payment bond. If work doesn’t start within 90 days of recording, the notice expires and must be re-recorded. Payments made after expiration are considered improper under the statute and can create real problems if a subcontractor later files a lien.4Justia Law. Florida Code 713.13 – Notice of Commencement
Notice to Owner
Subcontractors, sub-subcontractors, and material suppliers who don’t have a direct contract with you must serve a Notice to Owner to preserve their lien rights. The notice has to be served before starting work or within 45 days of first furnishing labor, services, or materials.5Online Sunshine. Florida Code 713.06 – Claim of Lien Because you’re reimbursing subcontractor invoices in a cost-plus job, keeping track of every party that has served a Notice to Owner is essential for managing your lien exposure.
The Mandatory Residential Warning
For direct contracts over $2,500 on residential property of one to four dwelling units, Florida requires the contract itself to carry a specific lien-law warning in bold, capitalized, 12-point type.6Online Sunshine. Florida Code 713.015 – Mandatory Provisions for Direct Contracts The warning tells you that unpaid subcontractors and suppliers can put a lien on your home even if you’ve paid the contractor in full. The requirement applies to cost-plus contracts the same as fixed-price ones. The statute does not require this specific warning on commercial projects or residential buildings with more than four units, though the underlying lien rights still exist there.
Lien Waivers With Every Payment
Cost-plus contracts run on progress reimbursements, which means you need a system for collecting lien waivers at each payment. Florida law requires anyone receiving payment to execute a partial release of lien to the extent of the amount received.5Online Sunshine. Florida Code 713.06 – Claim of Lien Before final payment, the contractor must give you a sworn affidavit listing everyone who served a Notice to Owner and confirming those parties have been paid, or identifying anyone who hasn’t. Skipping this step is the fastest way to pay for the same work twice.
License and Insurance Verification Before You Sign
Anyone performing construction work in Florida must hold a valid license through the Construction Industry Licensing Board, which sits under the Department of Business and Professional Regulation. The contractor’s license number must appear on every contract, bid, proposal, permit application, and advertisement.7Online Sunshine. Florida Code 489.119 – Business Organizations, Qualifying Agents No license number on the cost-plus agreement is an immediate red flag.
The stakes for unlicensed contracting reach beyond bad work. A first offense is a first-degree misdemeanor. A second offense, or contracting without a license during a state of emergency declared by the Governor, is a third-degree felony.8Online Sunshine. Florida Code 489.127 – Prohibitions, Penalties An unlicensed contractor also has no standing to enforce a construction lien, which strips them of their main leverage against you.
Every contractor and subcontractor working construction in Florida must carry workers’ compensation coverage.9Florida Senate. Florida Code 440.10 – Liability for Compensation The general contractor is liable for workers’ comp payments to employees of any uninsured sub on the project. In a cost-plus job, before reimbursing a subcontractor invoice, confirm the sub either carries its own coverage or has a valid exemption. If an injury happens and no one has coverage, the exposure lands on the project.
Recovery Fund Disclosure
Residential construction contracts over $2,500 must also include a written statement explaining the homeowner’s rights under the Florida Homeowners’ Construction Recovery Fund, which offers limited reimbursement for financial losses caused by specified violations of Florida law by a licensed contractor.10Florida House of Representatives. Florida Code 489.1425 – Duty of Contractor to Notify Residential Property Owner of Recovery Fund The contractor has to include the Construction Industry Licensing Board’s contact information with the disclosure.
If Defects Show Up After the Work Is Done
Florida doesn’t let owners run straight to court over construction defects. Chapter 558 of the Florida Statutes requires you to serve the contractor with a written notice of claim at least 60 days before filing suit, describing each alleged defect in reasonable detail and identifying its location on the property.11Online Sunshine. Florida Code 558 – Construction Defects The contractor then has time to inspect and respond with a repair offer, a settlement proposal, or a denial. Filing suit without going through the process gets your case stayed until you do. The rule applies to cost-plus and fixed-price contracts alike.
Attorney fees and costs are recoverable by the prevailing party in a construction lien dispute at both the trial and appellate level.12Florida Senate. Florida Code 713.346 – Attorney Fees Fee-shifting cuts both ways, and it’s another reason to keep clean records from day one of a cost-plus project.