I highly recommend using RT for tickets, and installing a plugin called Asset Tracker. You can have multiple types of assets with different fields for each asset, link assets in tickets, use REST or their command line tool for automated queries/updates, and much more. It is all open source, modular, and very easy to modify.

While I agree on the price, as far as I know, the late fees are pretty much a thing of the past. If you rent say a 2 day movie, they tell you it is due 2 days later of course. However looking at your receipt you will see you don't get charged any extra fees unless you keep it 1 week past the due date. At that point you either buy it for whatever amount is listed on the receipt, or if you return it within 30 days pay a $2.99 (I think) restocking fee.