Some are found in or under parked cars or in tow yards, and a few have been found on roofs! (toniskittyrescue.org)
I live in an area where there are some pull - a-part places as well as auto parts places and towing yards where cars are sold. (mechanics.stackexchange.com)
The bright side of this is that most tow yards are surrounded by a massive fence and locked up at all times. (800loanmart.com)