Then everytime you switch between planes you have to retrim the plane as you will loose the trim. And if you want to stick to the hobby your best move will be get a better radio. As you will need it soon or later.
This isn't correct. Before computer radios became so inexpensive most of the guys I knew flew multiple models with what by todays would be considered entry level radios
Here's a few tricks to extend the life of your "entry" level radio.
1. Follow raideron's advice and set up both planes so the servos don't need to be reversed between planes. This isn't complicated it just requires some planning on your part.
2. Mechanically trim each model so that they are "trimmed" with the trim levelers set in the middle. You do this by flying it and then triming the model with the levers then adjusting the clevis one full turn of the clevis is about equal to on "click" on the trim lever so if you need 2 clicks up elevator trim then you land and turn the clevis 2 turns in the direction that will give up elevator recenter the trim on the radio and fly agian. After several "trimming" flights you will have a model that has been trimmed to fly with the levers centered do the same with the other model. Now all you have to worry about is making sure the trim levers are centered as part of your preflight.
Yes computer radios with multi-model memories make it easier to set up a model but it is possible to fly multiple models with a non-computer radio.