Shrug, you aren't the first to find out that an Airstream isn't for everyone, and you certainly won't be the last. Be glad that you found out before
you spent the money. I'm still trying to find out who told me "I'd rather ask a thousand questions before I write a big check than ask the same question a thousand times afterward."
You have been doing exactly the right thing in asking lots of questions. The answers may not have been what you wanted to hear, but at least you are listening to those answers. You are still young enough that your situation may (and probably will) change in the future, and an Airstream may well fit in your life then.
DW and I both like Airstreams, and we're still considering one for when we retire in a few years and become fulltimers. So far we haven't heard anything that would absolutely rule one out, but we have heard enough that there are a few caution flags flying. Like you, our finances are very limited, so we want to buy something that is as close to perfect for us
Airstreams are meant for traveling. It sounds like you will be parked for much of the year, but want the option to travel as time and weather permit. Here's a link to a 5er that PPL has for sale. 1997 Carriage Carri Lite 531RKS for Sale - F720 - PPL Motor Homes
Yes, it is in Houston, Texas, which is a bit far for you to go, but is something that might suit you.
You mentioned that the park is very strict on the age of the trailer. Does that mean that once a trailer reaches 20 years old it must go, or only that it must be less than 20 years old when it comes in?
Good luck on your searches.