It's a tough decision to make even if you have the money - PET scans use a radioactive tracer injected in your blood that's like 5 years worth of radiation in one day. It can detect cancers, but yea that's an unsettling amount of radiation.

Then there's the risk of them actually finding something, which is very stressful, requires biopsies, potentially surgery, etc.. for something that could actually be benign.

My gf did it already with no issues luckily, but I haven't been able to rationalize doing it myself.