If you are looking for a pool that you can put up in the summer and take down again in the winter then there are a few options – you could go with an inflatable pool (which would limit you to the smaller sizes) or a standalone steel framed pool could be just what you need.
There are many size options for steel framed temporary pools so you would need to consider how many people might be using it, the space you have available, whether you want to heat it or not (some heat pumps will only heat a pool up to a maximum size so keep an eye on that) and how deep you want it to be.
Taking the pool down when you do not need it will save on maintenance costs and water over the winter as well as keeping the pool in good condition by storing it in the colder months. You may also not want to have your pool standing in the garden the whole year round. And this is ignoring the fact that it may not be warm enough to use it for a lot of the year!
There are a number of steel framed swimming pools and it is best to make sure that you get one that will have enough room for the family to use and also one that comes with its own pool pump/filter (not all stand-alone pools do but the bigger ones should do). You will need to buy chemicals to keep the pool water safe and clean but these can be found at any pool supplies store or even online.
You can also buy a separate heat pump or solar heater for the pool. It depends on what you buy as to how much it will heat the pool up – solar heat covers and generators may only heat it up by a few degrees – so consider how warm you might want the water to get.
Obviously another benefit of having a temporary pool for your garden is that you can take it with you to your next home when you move and it will not put people off buying your home (as pools can be shown to put people off who may not want the hassle of the upkeep).
