[Closed] Plumbing quotes

I'm having an extension built at the mo, extending my dining room and kitchen. I've expanded my plumbing requirements since the building has started from a simple boiler move and replacement to a full conversion of the vented system to a vented system and a top of the range Valliant Eco boiler and wet underfloor heating. The underfloor heating comprises of the normal wet underfloor setup in the extension part (3.5m x 8m), but in the existing house with concrete floor it would be a surface mounted wet system (3m x 8m). I've been quoted £3500 for the system conversion, which I think is probably what I was expecting. But for the underfloor heating I've been quoted £3k, which sounds a bit steep, considering the extension half is a bit of insulation and plastic piping In the extension part, though I don't know much about these surface mount wet systems suggested for the existing part of the space, but still sounds a bit steep.

Has anyone got experience or a feel if these quotes are in the ball park? I don't want to get a 2nd quote as the builder is doing a turn key job, so I'm not dealing with the trades individually. Cheers.