Know this has been done a bit before, and am studying the threads but if anyone could give me an inkling about the costs for the following that would be marvellous. DH and I will be having a pow wow about this this week.
Three/Four bed terrace house in the expensive part of the SE
In the end we need a ball park, are we thinking £50K? £70K? £100K?
Architect to do plans / project manage Total rewiring Install central heating New Kitchen Bathroom WC 2 storey extension for kitchen / other bedroom Replastering
do not let an architect project manage, he will bankrupt you (unless you are planning something drastic eg ripping out the whole of the back wall and replacing with plate glass or similar, in which case you will be bankrupt anyway)
either get a project manager who can also do the plans, or get an architect and a project manager separately.
NB your budget doesn't appear to include decorating, carpets, garden or contingency (for when they find knackered roof joists / dry rot, flood the bathroom etc)
Have you planning permission for the extension? If not are you sure you will get it?
If you find a good builder you probably won't have to shout at them and they will turn up!! You will need architects plans drawn up and approved through planning and a good builder would manage the project. An independent project manager would probably charge 10-15% of the fee.
I would estimate the works to be in the region of £100k - depending on type of kitchen and bathrooms.