Help to Buy Mortgage?

Hello Moneysaving people :)

Myself and my wife had been diligently saving for the last year for a mortgage deposit, which we had finally managed to do. However i have recently taken a new job, which came with a relocation to a much more expensive area to live.

So, at the moment we're still renting. However given the announcement of the new "Help to Buy" scheme we have been tempted to look again at buying. We have enough money for a 5% deposit, so if we looked at an eligible new build we would only need at a 75% mortgage, i think?

That's what i am not really clear on, i assume the 20% would go direct to the developer and we would pay the remaining 5% and the mortgage company the 75%? If so, do i need to find a specialist mortgage, which will accept the "Help to Buy" scheme, or, can i just get any standard mortgage? I am with First Direct for banking and there mortgage rates look very competitive, but they don't seem to like most of the shared equity schemes?

Sorry, this may be a rather stupid question, i will also be seeking a mortgage advisor at some point anyway as my wife is "Self Employed" so there are some additional complication.

Thanks in advance for the help as always!

Gareth