Welcome.
But, why are you asking a bunch of strangers on the net this question? I'm not going to tell you what to do, you are TWENTY ONE years old. It's really old enough to decide what to do on your own, do you not think?
I can tell you what *I* would do, and it would be to sit down and have a (well you should try) to have a mature conversation with them about your vaping, and see if they are comfortable, and if they are not maybe the garage or you should vape outside.
The fact your parents found you 3 times already tells me you aren't good at stealth.
At this point in your life you don't NEED stealth anymore, you just need to find out if you are vaping INSIDE or OUTSIE and well if you can't vape in your bedroom there are INFINIUDES of places you could find where you make your own rules. If you are working or in college you should find a part time job and go for THAT.
I worked part time ALL the way through college and graduated with a double distinction in both majors so don't get all whiny if you are in college about funding yourself to get your own place.
Anna
But, seriously I could care less which choice you make. Your parents may have a different opinion but it is THEM you should be talking to.
Oh boy the educational system has so much to answer for these days.