I've been looking at houses for sale, specifically something with an existing flat or something that can be converted. Recently, I saw one which currently has a free-standing (detached) workshop. It has a shower/toilet/laundry sink. The rest is as you'd expect such a building to be— basic brick with concrete floor. The only thing else is a drop ceiling of white rectangular tiles. The size is roughly 6m x 6m.
The question is: what would be a minimum price to finish off the inside & weatherproof such a building? We're happy to simply paint the interior ourselves and hope to find 2nd-hand salvage cabinets to set up a tiny kitchen. What I'm concerned about is what should be done with the floor & whether a french or sliding door would be a viable replacement for the garage door. Lastly, some of these we've seen have a breaker box inside the building- would this have to be moved?
I have no idea what this sort of renovation would entail and appreciate possible guesstimates/ideas from those of you with renovating experience. I do realise that building codes may vary— I'm more trying to get an understanding of "must do/must have this" in most cases.