You might come across an ad promoting super-low fares for a rental car service you have barely heard of. It looks good, but you just want to make sure it really is $50 cheaper per day and call the number.

They will confirm the price is right, but when you get there your car is unavailable.

This is a common scam pulled by centers that are located far away from populated areas or airports; the customer has wasted a lot of time getting there and doesn’t want to go somewhere else.

That’s when unwanted upgrades and insurance add-ons are stuck to the bill, making the final invoice even more expensive than it would have been at reputable rental companies.

How to avoid: just like all the other rental scams, this one invites you to use the best rental companies out there.