How many quotes should I actually get, and does the middle one win?

The folk rule about taking the middle quote survives because it feels prudent, and it substitutes a rough heuristic for the work of actually comparing what each contractor proposed to do. Three quotes are worth getting. What matters is what they say.

Make them comparable first

• Give every contractor the same written description of what you want, so they are pricing the same job.
• Ask each for the scope in writing, including inclusions, exclusions and materials by name.
• Ask each what they expect to find that could change the price, which is the most revealing question you can ask.
• Compare the exclusions, because that is where the difference usually lives.

What a very low quote usually means

• Less preparation, fewer coats, thinner materials or a smaller allowance for making good.
• Exclusions that will return as variations once work starts.
• No allowance for waste removal, access or protection.
• In some cases, no insurance and no licence, which is where the saving actually comes from.

What actually separates them

How specific the quote is, how they answered the difficult question, whether they turned up when they said they would, and whether the licence and insurance check out. Those four predict the outcome far better than the number does.