Establishing a new congregation in a city, even if it’s part of a well established denomination, does not guarantee finances to build.
Often there is short term assistance, with the new congregation providing most of the funding. It still doesn’t allow for much more than adequate facilities for a time, or while a building project is going on.
Oh, I know. It takes some time. Heck, the great Gothic cathedrals took centuries to build. I was more addressing the fact of the existence of other denominations. ;-)