Any Estate Sale Reselling Tips?

I've had some pretty luck looking through local Estate Sales locally and fixing then reselling bikes but I would like to expand to more. A lot of the online stuff is pretty competitive and I am uncomfortable bidding for something I can't personally inspect (feels a little bit too much like stone gambling) so if possible I'd like to stick with local listings. Unfortunately bikes are really the main ones I know enough about to tell what they may be worth and how much it would be to fix them up etc.

I'm not looking for huge ROI or anything, just something I can keep my eye out in local listings that I can be reasonably sure wont sit on a shelf for a long time or be broken in a way I won't discover until after purchase (like old audio equipment) and wont need a truck to move. A lot of the stuff at the estate sales around me is pretty vintage (60's-80's) so it's kind of niche in that way too.

Any suggestions for stuff to look out for would be appreciated.