Used from vehicle rental

Hello everyone, I have signed up here once, because there is a change of vehicle in the foreseeable future. After a long search my wife and I agreed on a Mercedes B-Class because it corresponds to our ideas as far as possible. However, it should be a young used one, because I am not willing to spend a lot of money for a rideable kit, which in a few years is worth only a fraction of the original purchase amount. In the used car segment I have various Offers from the vehicle rental were noticed, which I would still call relatively cheap. However, I cannot estimate the value or the risk of these offers. Therefore, I would like to hear from you your opinion about it. Can one(s) strike there undeniably, or should one leave the fingers of these offers. I am very curious about your opinions 🙂 Greeting Fritz