Dangerous Heatwave & A/C Died

I posted about 2 weeks ago that my climate control was making odd noises. But it was still blowing ice cold and working fine.

Based on the lack of responses to that post, I wrote the noises off thinking I might be making a mountain out of a molehill.

But the noises got worse & worse over the course of the next 5 or 6 days, until the a/c started blowing hot air on the 27th of June.

To say that it has been a TERRIBLE week would be an understatement. I've gone though the worst heat wave in 20 years while living in my car with no a/c. Had to check into a motel for a few days as my health was suffering.

I've been to 3 mechanics thus far...

The first shop did a diagnostic and found nothing wrong. Pressures were good, etc. This was probably because the a/c was still blowing cold at that time, and it was also in a shop out of the harsh sunlight, so the load/strain was much less (no noises).

The a/c died the next day.

I then bought a used compressor and had a second mechanic install it for me, along with putting in new freon. He initially told me that the compressor wasn't working, but when I picked the car up the next morning he said that everything was fixed! It was blowing freezing air while in the shop. This mechanic also said that my "low switch" was disconnected and that "might have" been the problem. About 20 minutes after leaving the mechanic the a/c started blowing warm again...like heater level warmth.

Took it to a third mechanic who said that - based on everything I explained - it could be the expansion valve. He replaced the fuel filter (strainer & cotton pad) and upon inspecting them, we could see tiny metallic particles on them. This is when we started to think that the system grenaded. Which might explain the very loud noises I heard before the a/c went hot.

He checked the pressures on each line and they were way out of whack and acting unusual. So he tried vacuuming/flushing the lines out to remove any debris in case there was a clog or to remove any of the metallic particles. This did nothing.

Today, he replaced the used compressor with a brand new one. He also vacuumed/flushed the lines again for a longer duration this time, to hopefully get any residual debris out of the system, along with removing the old freon and adding a new batch.

His thinking was: Let's try a new compressor first. If it works, great. If not, odds are high that it's the expansion valve.

After completing all of this, the pressures were both stable and normal this time. We started the car, and, once again, the a/c was blowing ice cold. However, within 15 minutes of leaving his shop it was blowing warm, just as it did before.

This debacle has cost me almost $1,000 and I'm still stuck at square one.

If it's the expansion valve, there's no way I'm getting that done. It's a tremendous job that requires 6-7+ hours of labor, in addition to the parts.

Is there anything else that this might be aside from an expansion valve?

The likelihood of THREE compressors being the culprit are astronomical (my original, the used one I bought, and the new one installed today).

Not sure if there's anything else that I can check, or if I should just sell the car as-is because I'll be moving into my camper soon.

I'd very much like to have the comfort of a/c over the next 5-6 weeks before the Prius is sold, as this heat is dangerous due to my health issues. And selling the car sans a/c will cost me a lot of money because I'd have to reduce its price by a lot.

Thoughts, please.