If they are questioning price before you start and asking about insurance etc then I would walk.
I bet they were a pain and went for the cheapest, when it went wrong the fitter didn't answer the phone and ignored them. Now they are trying to do the same. If you have already said that you will go round then walk in and give them a stupid price to fix it and walk out again better that than getting a bad name for not turning up.
If you do do it then do what you are happy with take photos of before and after. Me personally would want to repipe it back to copper as if one joint has popped then the fitter has done something wrong as they don't pop for no reason or at least I've never had it before.
I bet they were a pain and went for the cheapest, when it went wrong the fitter didn't answer the phone and ignored them. Now they are trying to do the same. If you have already said that you will go round then walk in and give them a stupid price to fix it and walk out again better that than getting a bad name for not turning up.
If you do do it then do what you are happy with take photos of before and after. Me personally would want to repipe it back to copper as if one joint has popped then the fitter has done something wrong as they don't pop for no reason or at least I've never had it before.