Cost Plus Contract Protection: The 4-Part System That Saves

Part two of the Cost Plus Contract series delivers the structure that prevents $100K+ overruns. If you caught Episode 56 last week, you know Cost Plus is when your contractor gets reimbursed for every cost plus profit margin on top—and it only works for three kinds of homeowners: the very experienced, the truly indifferent to total cost, or someone working with a great craftsman who's horrible at bookkeeping.If you went through the seven questions at the end of Episode 56 and your answer was walk away, you're done. Catch Episode 58 next week when we cover fixed price contracts. But if you decided Cost Plus is still the path—by choice, because that's what your contractor offers, because you're rebuilding after a fire, or because you're doing a complex remodel where Cost Plus is honestly the right call—this episode is for you.In the book, I talk about Cost Plus contracts like rappelling down a cliff. You can do it. People do it all the time. But you better secure the rope at the top before you start. This episode is all about securing the rope.The 5 Things to Settle Before Work StartsSettle these with your contractor before the first bill arrives, before there's anything to argue about:1. Billing Frequency — How often will you get billed? Once a week, twice a month. Most contractors bill on their payroll cycle. If they pay their crew every two weeks, they want to bill you every two weeks. Match yours to theirs. Predictable timing means you can plan reviews, set aside money, catch problems early. Unpredictable timing means you're always reacting, writing checks in a hurry, hoping to catch up later.2. Employee Hourly Rates — Each worker should get billed at their actual loaded cost: wages plus payroll taxes, workers comp, unemployment insurance, health benefits, vacation. On a worker making $30/hour in wages, you might pay $45/hour loaded. That's not markup—that's the actual cost of having an employee. The markup comes later as profit and overhead. Watch for double-dipping: some contractors tack P&O onto each individual hour, then add it again at the bottom of the bill. Ask upfront what's included in the hourly rate.3. Payroll Honesty — Every worker on your job should be on the contractor's actual payroll with full benefits and proper insurance. The loophole: some contractors hire day laborers, pay them cash, bill you the full loaded rate as if those workers were on payroll, and pocket the difference. It's illegal. It's insurance fraud. If a day laborer gets hurt on your property and the contractor wasn't carrying proper coverage, you can be on the hook. Ask for certificates of insurance for workers comp covering everyone on site. Verify them with the carrier directly.4. How the Contractor's Own Time Gets Billed — Your contractor spends real time on your project that isn't on site: ordering materials, meeting with your designer, calling subs, writing emails. Settle how that gets billed. Common arrangement: contractor's on-site time gets billed hourly. Off-site administration time gets covered in profit and overhead at the bottom of the bill. Pick one and put it in writing.5. Mistakes — They're going to happen. On a strict reading of Cost Plus, the homeowner pays for all time and materials regardless of whose fault. On a fair reading, when the mistake is clearly the contractor's, they should absorb it out of profit and overhead. Most Cost Plus mistakes happen because of poor plans, thin specs, and missing information. Have the conversation before you start, agree on how mistakes will get handled, put it in writing. When the inevitable happens, you have a framework instead of an argument.The Documentation DisciplineOn a Cost Plus contract, documentation is the protection. Every receipt, every bill, every supplier statement, every time card that gets billed to you should clearly identify your project. Pick a code—your last name, your street number, doesn't matter what, just be consistent. Don't pay for handwritten bills. Don't pay for receipts that don't identify your job.Every invoice from your contractor should identify which work breakdown structure category it belongs to. When an invoice is tagged to a WBS category, you can see at a glance whether spending is on track. Plumbing budget $20K, plumbing invoices to date $18K, project 60% done—are we on pace? You can answer that question. Without WBS tagging, you have a stack of paper. With WBS tagging, you have a project dashboard.Set a review window. Seven to ten working days is reasonable. During that window, spot check three line items, look at dates, check whether the time card matches the calendar and what you know has progressed. Call a supplier or two and confirm materials match what they say they're for. This isn't paranoia. This is professional billing review. Every commercial owner does it. You should too.The Hybrid Model: 4 Moves That Take Risk Off t