Side extension - Ball park figure

[muffinhead4]

We are in the process of remortgaging our property and hoping to release some further capital in order to complete a side extension. It would be roughly 20msquared and would include a kitchen referb and a utility room. (We are based in the south east) However we don't know how much extra to borrow. When asking for quotes we have been told they only quote off plans. We are reluctant to spend money on plans if the quotes come back too high we wont be able to go ahead with the project.
Where can i find a ball part figure quote? Any help as to where or what to do next would be great.

Try this company for an instant online quote, they were accurate when we got a side return. But don't use them - their reviews are terrible!

Online Quote Calculator | BuildTeam London

Minimum £3000/m2 then factor in budgets on top for kitchen etc depending on quality/level of finish. You could be looking at least £100K.

If it’s single storey can you not put together your own plan , my husband drew the plans for our rear extension and the builder just adapted them and put us in touch with a structural engineer ( I think that’s who it was ) to check the steels needed .

At the moment I think it's £3k per sqm to first fix, plus cost of kitchen, decorating, floors etc. Overall budget needs to build in ~25% contingency too. I'd probably aim for £125k for low-mid spec, £150k for higher spec