Our area's main post office moved into a new, large, purpose-built home in the 1970s. In the 1990s the post office moved into a small shop in the middle of one of the malls. Said business promptly went bust and, for a while, we had no post office at all. It then re-opened on the first floor of W H Smith's - all very well if you could get through the only entrance/exit and be able to fight your way through to the stairs or the lifts. When you got upstairs it had a small area at the end of W H Smith's stationery, art supplies and computer accessories department. On a busy day the queue stretches right round this.
Recently our local small post office (in the newsagent's) has closed, and they wanted to close down the quite large local branch office, which is slap bang in the middle of a reasonably sized shopping centre and is used by all the local businesses as well as residents. A petition was got up, and they have now reconsidered, although another large branch office about 4 miles away is still set to close. The only other post office I know of in our area is quite a walk from where I live with no bus service at all, down the sort of streets most people have no wish to go on their own when it is dark - even in daylight it can be decidedly dodgy. I don't even like going round there in the car!