In your case, I would recommend an above ground pool, that can be disassembled and keep your costs to a minimum. An in-ground model will cost much more, for preparation, install, and that all-important, regular, ongoing maintenance. You get the benefits, while you are there, and don't have to spend as much to install, prepare or maintain it.
Consider the investment to prepare the space, flatten it out, to be useful in the long-run, since that space can easily be transformed into other outdoor lounging, garden, gazebo, patio, deck, etc. once you remove the pool. These things are more valuable selling points, and if done well, can easily translate into higher resale values, with greater curb appeal. Turning the space into something a bit more usable, for entertaining is usually money well spent, and may even permit the home to sell faster, once it does hit the market.
You will not get the return on the investment, other than the personal use factor, an convenience, access to the pool vs paying for membership to a YMCA or other community pool. Going above ground will also give you the ability to determine how much it might get used, without incurring all of the expense, and tear it down when it isn't needed any more.