We are nearing completion of our self-build and have received an unexpected bill from our plumber. It's not huge but we have been messed around quite a bit and I don't want to be taken advantage of. His quote allowed for the supply of "1st Fix materials which includes soil pipes, waste pipes, hot & cold services, heating pipe work, pipe work to kitchen & bathrooms". He has now invoiced us £350 for "supply of pan connectors, shower fixings, basin/sink/bath traps, copper, waste pipe and fittings". This relates to three bathrooms and utility/kitchen sinks and all traps are the simple white plastic type. We supplied bathroom suites and our understanding was that all pipework would be supplied by the plumber. The distinction that he appears to be drawing is that the items now being charged for relate to 2nd fix materials which he has supplied (but not quoted for) rather than 1st fix materials (which he did quote for).
I would be grateful to hear opinions as to whether the items now being charged for are indeed "2nd fix items" and if so, whether the plumber's approach/price seems reasonable?