If the home as a pool/spa, you may not be able to get the spa heat without the pool heat. Some homes have the capability and/or will separate out pool and spa heat (with cheaper amount for spa heat only).
Also, the direction a pool faces is important; a south facing pool will get sun for most of the day--north the coolest, east the morning sun, etc.
Some homes use a pool cover October through May and utilizing this feature will also keep your pool warmer without heat.
We have a south facing pool and I would say around the time you are going it would heat between 78 and 82 degrees without the heat. However, mornings and evenings would be coolest when you want to use it.
With the pool heat, you have probably 86 to 88 degrees--spa heat 100 to 102degrees, mot likely. However, ask the owner to what temperature they heat the pool.
Otherwise, it depends on preference and how often you will use the pool, as well as time of day, etc.
I hope that is helpful. Best wishes for the greatest trip ever!
Sandy