did you actually see the carproof?
man, I wish my customers were this trusting. and hell, I actually deserve the trust! don't take a persons word on a carproof... and it also would have shown "registered as fleet" as the first owner. we have things like carproof/carfax and the like... USE them. in Manitoba, I don't think you have any specific protection agency, so it is just up to the good old fashioned putting up a stink to get your money back or whatever.
anytime you are asked to sign something like the form above, ASK what it is, and ASK why certain parts aren't filled out or completed. likely the was a police report or something on the carproof with no dollar figure. tends to be the case with rentals.
if you want to give me the last 8 of the VIN I can at least give a bit of Chrysler background for you...