I personally havent done this, but I know of some people who have - actually make that only about 2 family friends.
Overall, it's only really done here by people who've got some serious capital saved up. Not very many people have 2nd houses in which to live whilst their self build takes shape.
However, it is done and there are various companies which specialise in this, I remember seeing an advert in a property publication about self build and thinking sounds good - if I had all that money lying around!
In the cases of the people we knew who did it, they decided to project manage themselves, ie take on all the headache. Plus points is once it was built, I think they paid something like 600 grand, it was immediately worth something like 725 grand, so an instant profit of £125K. had they gone through consultants/management types I'd have expected their charges to have amounted to 40-60K.
There were figures somewhere and the %age of people doing self builds in the UK is very very small.
Restorations, depending on how dilapidated the original building was/is are different, but sometimes with similarities (ie pull down the old ad re build new) and other times it's just a complete makeover and re-arrangement of rooms etc.
Again, usually done by people who have the investment dosh to actually complete the work - although recently, more and more private people have been buying up properties which need minimal amounts of work in oder to just sell on (ie 5-10000 worth of renovation) with profits ranging from a few grand to maybe if they're lucky 5-20 grand or so.
Trick of this - Know people who are reliable and can do the work at a good price in order to maximise your return on investment!
Tip for self build - have LOTS of money in the bank!
Cheers ! DtM, West London !