Accepting Quotes and devis
Quotes need to be accepted in writing. If your written French is poor, a couple of sentences saying ‘We accept your devis of [date], number[ref]. Please confirm how soon you can start’ should be managed.
It is sometimes suggested that you try adding a clause that the quote be conditional on a certain start or completion date.
I doubt if this will help you too much. Even if the dates (and the whole devis) are not rejected by the builder, there will be little you can do about it if the work does start late. Are you seriously going to take the plumber to a French court if he is behind schedule? I know some people like to try and insert penalty clauses in case a delay occurs. In my opinion, developing a positive relationship with your workers will get better results, but you may consider it worthwhile.
I recently received a query from someone who had paid a 25% deposit on a new roof, with the work due to start in a month or two. They had now decided not to proceed with the work for personal reasons. In this particular situation the problem was unavoidable, but do try and be sure that you only accept a quote, whether or not you pay a deposit, if you are completely sure that you want to proceed with the work. Otherwise you will create a difficult situation all around, if the workers involved have bought materials, postponed other work and so on to fit your work in.
Don’t accept an estimate unless you actually have the money to pay for the bills when they arrive! I know someone who borrowed the money from the bank to renovate a gite. The gite didn’t generate enough income to pay the loan, and the bank are now forcing a sale of the property.
File a copy of the letter that you sent accepting the devis.