This is a very common problem that unfortunately is usually worsened by ignorance. It's also something to take into consideration if you're ever to buy ( or sell ) a used car, as it usually has an easy solution that shouldn't impact on the final price of the vehicle.

If a car will not quit blowing fuses, it's for a simple reason: something is wrong with the circuit. That makes the amp load of some part of the car's circuit to go above the limit of the fuse, therefore blowing it. This happens precisely to protect the system from an overcharge.

Now, the wrong solution for this ( if the car is yours ) would be to install a larger fuse, as you risk damaging the entire circuit or even a fire. What you should do is let an expert check all components in order to determine the real reason behind the blowing of the fuse. It could be a connector short, a shorted motor or something else. The important thing in these cases is not to make things worse and ask for help.

Also, if you're checking the condition of a used car you're about to buy and you come along something like this, don't panic. Just tell the seller you'd like an expert take a look at this and act upon what he finds.