OK, I got answers to some of these ....
1. There will be fibre run in to each of the flats from a central DP node in the complex somewhere. Within the flat it is often located in a utility cupboard.
3. It can depend on a few variables. When I do similar installations in the flats by Newbury racecourse, I will have to fit the the ONTE and CSP in the flat. Then fit a light source, identify the fibre in the DP node, splice here and also at the splitter node out side. All this takes a fair while.
It may be that more of this work has already been completed, there are properties in Wokingham where it is all in situ when the punters move in, and the owners just need to order service.
4. Sorry, I don't know this one.
Good luck, and keep us posted.