Mustang Questions

[HabsForever]

Hello everyone.

I turned 17 last November and got my license the following January. I live in a middle class family with a newly single mom who just got herself a somewhat decent job. I am currently driving her car, a 2008 Avalon XLS which I do like, but it's becoming too big of a hassle for the both of us and it's time we start looking into cars for myself.

Now, it's always been a dream of mine to own a Mustang ever since I was playing with Matchbox cars as a toddler. I also love American made cars, a value which as you can tell skipped a generation in my family and doesn't really matter to my mom.

A long story short, the maximum budget we're dealing with here is likely around $5,000 (Just for the car, not including insurance or anything like that), and the lower the better. I will need an Automatic transmission. Based on that, I have a few questions.

What is the latest year I can expect to find for a price like that?

What type of mileage should I expect for those demands?

Where should I look for it?

I also want a convertible. Is this realistic for now, or based on my needs should I save that until I'm older and have my own salary?

Should I just scrap my Mustang dream until I'm older and have my own job, because I won't be able to find a decent one with my demands? If so, what car should I try and look for instead?