You should have minimum 5 ft but 6 ft is ideal. I've played pool where tables are 4 ft from the wall and it is too close. The standard pool cue length is 57" and the draw length is about 6" so 5 to 6 ft would be ideal.

Personally I think you are better to wait until you can afford to put back an in ground pool as the one's that I have seen sitting above the ground look like an eye sore - a temp pool - that looks like it could collapse at any time. Maybe while you save for the bigger project you could rent / buy a large Spa Pool.

I'm glad you guys are growing.

Swimming pool season is upon us, rather late I might add this year, you may be considering painting your pool. There are a few things to consider is what the previous coating is and the appropriate preparation that is required. When we quote pools we generally only get to inspect them with water in them. We will always put a clause in to assess what the actual condition is like when empty, like when we found a good portion of the surface was very drummy and subsequently we had to remove a lot the surface and replanted, always be mindful of hidden costs when pool painting, they are not always straight forward.