The pricing mistake is not choosing wrong. It is never saying which one you chose

Day rate, price work, fixed quote. There is no correct answer. Different jobs suit different models and any of the three can be the right call.

Almost every pricing dispute I have seen started somewhere else entirely: nobody said out loud which one was being used. The customer walked away thinking they had a fixed price. You walked away thinking you were on a day rate. Both of you were being honest. Six weeks later one of you is wrong and it is going to be an argument.

Here are the mistakes that actually cost money, in the order they cost it.

Mistake 1: saying "quote" when you mean "estimate"

These are not two words for the same thing, and the difference is legal rather than stylistic.

A quote is a fixed price. An estimate is a rough guess. And the part most trades do not know:

Once the customer says yes to a quote, it is a binding agreement, whether or not it was written down.

Said in a kitchen, over the phone, in a WhatsApp voice note. If you called it a quote and they accepted it, you have agreed a price. There is no "I only meant roughly".

There are three ways you can charge above a quoted price, and only three:

1. The customer asks for extra work that was not in the quote.
2. You tell them extra work is needed and they agree to pay more for it, before you do it.
3. You made a genuine mistake writing down or calculating the price. You can charge what it should have been.

Notice what is missing. "It took longer than I thought" is not on that list. Neither is "materials went up". If you are not confident enough to fix the price, do not use the word quote.

On an estimate the position is looser: the final price has to be reasonable, and the law does not define reasonable, so you and the customer have to agree what it is. That sounds like freedom. In a dispute it is the opposite, because "reasonable" is decided by whoever is more convincing, and the person holding the paperwork usually wins.

Mistake 2: pricing a day rate off your old employed wage

This is the one that quietly runs for years.

You were employed on the equivalent of £160 a day. You went self-employed. You charge £160 a day, because that is what you are worth and that is what you used to get.

Except it is not what you used to get. It is what you used to get plus everything the employer paid on top that you never saw.

Do the subtraction properly. There are about 260 weekdays in a year. An employed worker is legally entitled to 5.6 weeks of paid holiday, which is 28 days for a five day week, and bank holidays usually come out of that. You get none of it paid. So before you have been ill once, or lost a day to weather, or spent a Sunday quoting, or chased an invoice, you are already down to around 232 chargeable days.

Then take off the real ones. Sickness. Bad weather. The day the job fell through. Quoting and site visits you never charged for. Van off the road. Admin. Chasing money. Nobody sells 232 days.

Run your own numbers rather than take mine, but the shape is always the same: your chargeable days are a lot fewer than the calendar suggests, and your day rate has to carry all the ones you do not sell. Plus your tools, your van, your insurance, your pension, and the tax you now pay yourself.

A day rate that matches your old wage is a pay cut wearing a pay rise costume.

Mistake 3: price work with no written scope

Price work is a good model. Both sides know the number, you get rewarded for being quick, the customer gets certainty.

It falls apart the moment anyone asks "while you are here, could you just...". Without a written scope you have no line between the price and the extra, so every addition is a conversation about goodwill rather than money. Do that four times on one job and you have worked a free day.

The fix is not a contract full of legal language. It is one paragraph saying what the price covers, and one saying what happens when something is added.

Mistake 4: switching model mid-job without saying so

Day rate for the first fix, then "we may as well price the rest". Very common, entirely reasonable, and almost never written down.

If it is not confirmed in writing, you now have a job where neither party can say what was agreed for which part of the work. That is the worst position to be in when the final invoice lands, because your own records disagree with each other.

One message. "Just to confirm, first fix was day rate at £X per day, second fix is priced at £Y." Sent the same day. That is the whole fix.

What I would actually do

• Use the word you mean. Quote for a fixed price. Estimate for a guess. Never use quote as a friendly synonym.
• Say the model in the first line of the paperwork, not buried in the total. "This is a fixed price quote" or "This is a day rate of £X, estimated at Y days."
• On an estimate, say what would change it. Ground conditions, access, what is behind the plaster. An estimate with named variables is far easier to defend than a bare number.
• Work out your chargeable days once, properly, and keep the figure. It is the number your whole day rate stands on and most people have never calculated it.
• Confirm every model change in writing on the day it happens. Not at the end, when it is your memory against theirs.

The detail

This is the top-of-funnel version. For a proper comparison of the three models, when each one actually suits the job, and how to structure the paperwork for each, the guide does the work: Day rate vs price work vs quoted.

Use the guide to pick the model. Use this to make sure the customer knows which one you picked.