House renovation costs

[Leirope]

We're currently completely renovating a late Victorian terraced house, six beds (one of which will become the master en-suite) and five storeys in the SE.

We've instructed an architect to help draw up plans and basically project manage the build as we're up in London most of the time. However, we're a bit concerned with the pricings that the builder she works with is coming up with. It seems very difficult to get him to give us a detailed breakdown of costs and one of estimates he's given us for plastering is working out six times more expensive than a quote we got independently (£18k vs £2.8k).

Is this normal? Would we be better getting our own quotes and trying to instruct our own builders where this works out cheaper and just suck up the ensuing stress this will cause? If anyone has done anything similar and is able to offer the costings for work they had done it would be really helpful.

Have you been through a tender process to choose the builders? Surely this would get sorted out then. Or are you just at an estimating stage?

The architect should draw up tender documents and get a variety of quotes. Therefore it is the responsibility of the architect to draw up detailed tender documents, but are you at this stage right now and are you paying for this service, or just plans and project management of the build?

The difference between the plastering quotes you have received is too great. Have you asked for the identical area of walls/ceilings? £18k sounds too high, but £2.8k sounds a bit low for a 5 storey house. Does the higher price include tanking a basement for example?

Only take on letting separate contracts yourselves if you really, really, have the time and you can live with the hassle. It will be immense. Your builders/trades will not work effectively with the main builders and you will have to dovetail when they do the work so it ties in with the main builders requirements. Good luck with that if you are not living on site. Everything that goes wrong will be blamed on you.

Everything costs more than you think. Things go wrong and cost money and time to sort out. If you an afford it, let the professionals do it.