Help

I have asked every mechanic and been to every shop looking for an answer to the following problem but in vain!

When I bought this used van, A/C was working. Some time later (more or less a year later), I have noticed that the fan switch stopped working except on the highest setting [the fan will not work when it is set on 1,2,3, or 4, but it works on 5.] I had no choice but to set the fan on 5 if I wanted to have cool air. It was bothersome, but I did put up with. After several months of using the fan on 5, the cool air stopped all together. Even when the fan is set on 5, only warm air is coming out. I took the van to several mechanics, but I kept getting different opinions like compressor is bad, there must be a leak somewhere, freon level too low, blower motor resistor not working, needed a/c blower motor, etc… In short, one mechanic told me that there is no leak, another mechanic put a new blower motor resistor, a third mechanic changed a/c fuse… but none worked so far, and the problem still exists. Right now, if I put a new a/c fuse, good, cool air will come out for just a few minutes, then the fuse blows out. I change a fuse then I turn the a/c on,just to have the fuse blows up again… I have spent alot of time and money on this problem and still do not know what to do to fix it. I have no faith in the dealership that’s why I did not try that route.

Please advise.

Thank you.