Unfortunately another aspect of this situation which hasn't been brought up is that in our sue-happy society I wouldn't be at all surprised if you found yourself liable for her actions while driving your car.
Pretty sure you could find her in about 20 minutes with the rescources available on the internet.
Thanks for all the advice guys. Looks like me threatening her that I was going to have it reported stolen helped. She will have it to me by the weekend so she says...And yes I have asked her over the phones several times for it..she basically said go screw yourself. But at least this time it worked..just sad that I had to threaten her to get it back...sad state of affairs really...
Reminded me when my cousin took my iPhone 4 a couple of years ago, then lost it
I wouldn't wait. Go to DMV and cancel the registration NOW - This may help you with any liability issues. Also, should your sister (pics pls) be stopped by a cop and the registration is no longer valid - They will automatically tow the car, and that will help you get the car back.. . . Or let the registration lapse on it
