Maxima 2006 automatic did I get taken advantage of?

Long story short, I took my car to a mechanic because it would overheat whenever I drove with the AC on. The car had also been sitting outside and hadn’t been driven in about two years.
He recommended the following repairs, including labor:
Radiator fan: $300
Valve cover gaskets: $380
Rear brakes: $180
After the repairs, the AC was still blowing hot air. He added Freon for free, but that didn’t work. He then said I needed a new AC compressor:
Compressor + labor: $420

My question is, could he have known from the beginning that the compressor was bad? I understand the other repairs may have been necessary, but my main reason for bringing the car in was the overheating with the AC on.
Does this sound like a normal diagnostic process, or did I get taken advantage of?