Garage conversion/new kitchen - advice?

preciosa

I'd love to convert our integral garage into a proper room, ideally a new kitchen as the one we have is quite small. Anyone got any idea how much this would cost and can anyone recommend a company in the Kent/South London area. I've heard that specialist companies are very expensive, could I get any builder to do it to building regulation standard. The previous owner started it by putting a wall inside the garage door and putting power points in but I don't know if these were done properly. I woud like a proper window put in instead. Do building control check after work has started as I don't want them telling us to remove what's already been done.

Where can I get a decent cheap kitchen? Possibly a freestanding one so I could get it now and move it into the new room later. I suspect making it a kitchen would cost too much so I could go the cheaper route and just make it a playroom or dining room. I'm not sure exactly what work is involved. I have an uphill struggle to persuade my husband it's a good idea so need to present him with some facts and figures. Would it increase the value of the house?