For a farang, buying a lease with all it's attendant problems, abiding by the regulations and the plod's you know what, dealing with Thai staff, and competing with hundreds of other similar businesses run by Thais, it's almost designed to fail.
I used to visit a well known and long established restaurant owned but not run by an Englishman near the Coconut bar, so in a prime location ( he wasn't allowed to make himself breakfast in his own kitchen ). He gave up and went home because the plod became too demanding.