I fully understand where you are coming from on this one. My advice, get the most inexpensive trainer that still has good quality. Spend money on a radio and engine that you can remove from that trainer and put into your second plane. If you fly quite a bit, you very well may be bored and done with that trainer in short order. Some people continue to fly their trainers ... most don't from what I have seen.

If a local field will let you use their trainer, even better. My trainer is now in the basement and not being used at all. I'm going to donate it to my club where it will get some use.