The worst case is not the condenser or compressor. It is the evaporator.
It looks like this.
To diagnose this one, you need the assistance of an AC specialist who will put magic smoke into the system to spot leaks.
It costs about three grand. Buying it is only the first part. It is a boat load of work to replace.
You are looking at a ten grand job. Happened to my E46 a few years ago.
Luckily this is not the case here.