We self-funded as we had a substantial sum to invest and now finance it 50:50 through personal and bank as it cheaper to borrow and leave our funds in investments.
I was an IT consultant for a few years but we have experience of self-build and major renovation. We partnered up with our friend who was a builder by trade so we have a builder head and a business head. Running a business always requires the same issues, scheduling, financial control, supply chain management and staff management. We have 23 staff now who we look after well, they in turn look after us.
Compulsory Purchse Orders are rare nowadays, local searches when buying land should tell you if there is anything untoward happening nearby which would affect your build or sales. Planning issues are the pain in the butt but remain calm and patient and keep within the regs and you will get there. Got to have a thick skin when it comes to locals as well s they will kick up an almight fuss no matter what you do - even if that is what you asked for. To give you an example...
We proposed eleven executive houses on a two acre site, the locals objected and complained like hell and said they wanted to see smaller, affordable housing on the site. We resubmitted for a small estate of "afordable housing" and they went even more nuts when they realised that it was - to the local gov't - acceptable but would result in a different sort of resident in the locale. People don't like change but they don't like things to stay the same either. If you want to try it then start small, buy a house, fix it up and sell it on - see how you got on with it before tackling bigger jobs and use a good builder - even if they cost a lot more - it's worth it.