Yes, car rental is expensive compared with USA, generally the rental start at 60 cuc ~ 70 usd per day with this car (Hyundai ato 2009)
plus the insure that is around 300 usd, returnable at the end of the contract if you don't have any issue.
There are others alternatives, like rent a car to a natural person, in this link you can see the cuban version of craiglist