Ok ,no worries,

You would be best having a word with a few local builders in your local area of col de essex, make sure they are FMB (Federation of Master Builders) Registered, http://www.fmb.org.uk. Ideally try and get three or four quaotes, and make sure you qualify any gripes they, or ou may have with what you intend to have done, it is only a garage base, but issues still need to be sorted, whatever the size of project.

I always try to get three quotes (makes sure its a quote, not an estimate) on all work I have done.