Mistakes I’ve made

When I went into the service I loaned a complete system (receiver, TT, speakers and a few records) to a friend.  It was the 70s, I was young and it was a 10 year old Radio Shack system, but top-of-line for them.  I come back from overseas and he is married and at a BBQ at his place with many people he announces to everyone what a great wedding gift I had given them!  I was essentially apoplectic.

That was the first and last time for that sheeit!

The flip side is while overseas I bought quite a bit of "very good" stereo equipment, but had yet to receive it as part of rotating back to the states.
Still have some of it. And yes almost 50 years later it still sounds excellent.

I remember being mesmerized by hifi gear in PX catalogs in the 70's

Lot's of Mistakes in my life.  "Loaning" out motto,
"Never loan out anything I or you are not willing to give away"
Stereo equipment, tools, money, frying pan...

OP: Never regret being generous. It's a an admirable character trait and you will be rewarded many times over.