One cannot possible give any advise or experience even when asked on pinside, somebody else always knows better, another downvotes, another comes up with a speculation outcome, so on and so on.
The same stupid saying is always tossed around. That’s is “cash on the glass”
Cash on the glass often is a massive amount, as in murder for hire happens for a lot less money than the cash on the glass.
How many people actually check every single bill to ensure it’s not counterfeit. Hold it up, look for the security ribbon, check all the proof marking, take a counterfeit marker etc. I bet none, or very few, in that case there is just as much risk for losing out.
Here’s the reality, any transaction is risky for both parties, what if one gets robbed? What if a buyer receives stolen property? What if a buyer is casing out the sellers place for a later date? What if a check is fake, what if money is fake? What if your “cash on the glass” gets lost after a serious car accident on the way to the bank? The answer to all of it is you never know, you have to be willing to accept some risk with obvious reasoning or just never sell anything.