This may end up a good thing for some people. About 5 years ago, I had a heating/cooling contractor come out to repair my A/C unit. It had failed just coming into a very hot night, I called a local company which told me "first thing in the morning".

It got hot.

I went to YouTube and found a few videos -- I had already known about the two fuses leading to the A/C unit, mine were fine. I hadn't known about a capacitor that was used to assist the fan in starting and discovered that taking a stick off the ground, starting the A/C and whacking the fan was enough to make it run[0]. I ordered the replacement from Amazon[1].

I had forgotten to cancel my appointment and the gentleman with the company arrived mid-morning. Being that the unit was all of 5 years old, and I had a good understanding what was wrong, I wondered what I'd be told so I acted dumb. Wouldn't you know it? It turns out that "the compressor is no good", and that "the kind of compressor used in this isn't made any longer"[2]. I told him, "Ah, that's too bad, I guess I'll have to have my Dad come out and replace it" and sent him on his way. Two days later I installed the first of the two capacitors I purchased and had working A/C until early this summer. This time when it failed, I took the panel off, saw the cap was bulging, and replaced it. Fixed. For those keeping score, that's 10 years on an A/C unit that apparently had a bad compressor and required replacement 5 years ago.

The moral of the story is that a few minutes of time on YouTube can save a lot of money and literal sweat. If you have a professional that you trust, great -- if you don't, get a second opinion before dropping a large amount of money simply because the A/C repair company sent a sales-person out when what was needed was a technician.

[0] It wouldn't start on its own, but I could get the house down a few degrees below comfortable and leave it off for the night, at least.

[1] I called a few places the following morning and nobody carried capacitors that size, locally; Amazon was it for guaranteed 2-day shipping; I miss Prime. It also appears my capacitor isn't affected by the parts shortage -- there's several on EBay and Amazon at present.

[2] The technician (who was actually a sales-person) attempted to mix up energy efficiency standards and actual coolant formulations; I don't recall exactly what he said but I recall searching the finer points and discovering that I had a very high-end A/C unit, and the entire compressor was available in used/new forms. Oh, and mine is still "just fine".