I have an old SG I bought used for $75 over 30 years ago. Great action. Great guitar.
If it is still in good shape it would now be worth about 50 times what you paid for it.
As a teenager back in the 80s, I had a friend who wanted to trade me a mid 1960s SG with a Vibrola tailpiece and trapezoid inlays for a pair of cheap skis I had just received for Christmas. I turned him down. Those skis are long gone and that SG is worth well over $10,000.
The mistakes we make...