Please try and understand the problem before you fix it.
The AC system is basically Compressor + expansion valve + condenser.
A compressor's job is to compress the refrigerant gas.
When some one says you have to change the compressor, ask them what was the expected
pressure by the OEM and how much is it actually producing ?
This question alone will kill 99% of our ustaads.
An expansion valve is just as important as the compressor, and a dirty valve or a worn out valve
will not properly expand the gas enough to produce the cooling effect.
this also means that you can't just swap compressors here and there, A compressor is dependent
on the right expansion valve to do it's job.
Lastly, the condersor is supposed to cool the gas enough, and it's health is measure in not leaking and
allowing adequate air flow.
The filter must be clean all the time.
Hope that helps,
best regards.
