Can I pull out of this Sale

This is an interesting post, and an unfortunate problem.

Terry raises a good point about legal recourse, which is if the buyer can't pay for the work, it's unlikely that you will be able to sue and get any money (they can't pay if they don't have money).

You've also mentioned that it will cost more than deposit to rectify the issues.

That being the case though, here's what I would be pushing for:

a) Know your legal rights

b) Exercise your legal rights (such as sung for performance)

c) Assuming that the sale does not go ahead though, rescind the contract and get the deposit (will the agent want their commission though?) 

d) Rather than return the building back to its original condition, I'd be costing out how much to complete the work. It might be worthwhile talking to the guys doing the work now

e) Keep us in the loop so we can brainstorm with you

– Steve