Your question is very vague, you have not said if the total invoice is more than the original quote, what are the cash receipts for? I presume you have nothing in place a A1 Bespoke Ltd have quoted i.e. binding agreement etc.
Did you give a letter of intent or did you e-mail acceptance of his quote, if not you have no binding contract, again until you tell us what the problem is it is difficult to answer your query
Peter

A standard form of building or construction contract is a binding agreement between the employer for the building project and the building contractor who is responsible for carrying out the construction work.
They include full details of the costs and provision of labour, materials and services as well as plans, specifications, drawings, a schedule for completion, and any changes which have been agreed. The construction work including the cost and time-scale must comply with the contract.
Although you haven't got a formal contract you do still have a detailed quote and it may be worth speaking to a solicitor to see if they can use it to gain you any recompense from the builder you used.