How tradesmen lose money -- the boring leaks that add up

The maths most trades never do

Before you can fix leaks, you need to see them. Take your last 10 invoices and compare them to what you quoted. Add up extras you did not charge for. Multiply by 52 weeks.

Common picture: a plumber doing reactive work adds 20 minutes to most jobs as a favour. At £60/hr, that is £20 per call-out. If they do 5 jobs a day, 5 days a week, that is £500 per week in unbilled time -- £26,000 a year.

• Write down every time you do something not on the quote this week
• Count the jobs where you forgot a line item vs what actually happened on site
• Look at which customers pay promptly vs who you have to chase -- payment delays cost you cashflow interest and time
• Check your material margin: are you buying at trade and selling at trade?

Free extras: the biggest single leak

A customer says 'while you are here, could you...' and most tradesmen do it. Once. Then twice. Then it is expected. The problem is not the work -- it is the precedent.

The fix is simple but requires habit: variations get agreed before the work happens, not after. A quick message saying 'that extra socket will be £65 -- happy to do it today' takes 30 seconds and gets a yes or a no. Both are better than working for free.

• Never start additional work without written (or at minimum message) agreement
• Set a minimum charge-out for small extras: half-hour minimum or £45 call-out addition
• On larger jobs, include a 'variation clause' on the quote: changes priced separately at agreed day rate
• If a customer pushes back, remind them the quote covered the agreed scope exactly

Slow invoicing kills cashflow

Every day you wait to invoice is a day closer to the customer mentally filing the job under 'done'. Invoice the same day the job finishes or the next morning. If the job is long, invoice on stage completion.

Late invoicing also means you are financing the customer's project. A £4,000 job invoiced 14 days late is £4,000 you did not have for two weeks -- multiply that across every job and it becomes a real cashflow problem.

• Set a personal rule: invoice before you leave or that evening
• Use stage invoicing for any job over 5 days long
• Include your payment terms clearly: 7 or 14 days net, not 'when you get a chance'
• Chase at day 8 not day 30 -- polite but immediate
• Keep a simple list of outstanding invoices so nothing falls through the gap

Materials at net price: you are subsidising the merchant

Passing materials through at trade cost with no margin means the customer gets your merchant account rate without paying for your time selecting, collecting, delivering and checking. That is a service -- price it.

Standard approach: add a percentage margin to materials (commonly 15-30% depending on job type), or price a supply-and-fit rate that absorbs it cleanly. On large material orders, even 10% margin is significant.

• Never invoice materials at exactly what you paid -- your time has a cost
• Check supplier invoices against what you charged before the job closes
• For customer-supplied materials: add a handling clause -- if the tiles are short, that is their problem not yours
• Keep receipts for every material purchase: both for markup verification and your tax return

Underestimating prep: the classic tuck-it-in mistake

Prep is invisible to customers until it causes a problem -- which is exactly why it gets omitted from quotes and then done for free. Rip-out, levelling, priming, treating damp walls: these are real costs.

The fix: price prep as a separate visible line. Customers rarely argue it when it is named. If you go over on a prep estimate, you can show the customer why -- 'the floor was worse than expected, here is the variation'.

• Survey the substrate before quoting, not on the day
• Add a contingency line for unknowns: 'unforeseen prep at agreed day rate'
• Never include prep inside m² if it varies by job condition
• If you cannot assess prep before quoting, say so: quote for what you can see, note the exclusion

Quoting from memory, not structure

When you quote from memory, you forget things. Not big things -- little things. The silicone. The trip to the merchant for the last two boxes. The extra hour for that awkward corner.

A price book or template forces you to at least see the lines before you omit them. Even a simple checklist of your standard inclusions reduces forgotten items to near zero.

Where Pro Quoter fits

Pro Quoter keeps the job thread together -- quote, diary, invoice all linked to the same customer and job record. Extras and variations stay on the record rather than disappearing into WhatsApp history.

Built by a tradesman for tradesmen who want less paperwork and tighter margin: enquiry to measure to quote to invoice in one simple hub, mobile-first for the van and site.