fascia board

I'm about to embark on the replacement of the fascias and soffits on the back of mine and our elderly neighbours semi detached houses (if the scaffolder turns up lol). I've done a lot of research but want to clarify a few things before i get going on it - i'd like it to be done properly this...

Hi, Is there a way for the return wall fascia boards to run level at the top and hide the fall/pitch of roof on flat roof extension? It’s a warm roof, finished in GRP and I have soffits extending on 3 sides with furrings giving a fall to the front in to a box gutter. I’ve seen a few different...