Cheapest way to get costings?

Hi everyone.
I'm wondering if anyone can tell me how to get costings together to provide a bank to get a mortgage on a property needing some work inside. Any ideas?
Architects seem to cost a bomb.
I'd like to project manage myself and hire in when needed for example an electrician etc.

Try a Quantity Surveyor

QS, Building Surveyor or Engineer.

A builder friend might give you a quote but I notice a lot of them are getting QS's to do up their quotations now and are charging for quoting if detail is needed on paper. Can't say I blame them.