Question for ya

I have a Co-worker who wants to buy 2 lowers from me. I know its legal to sell without a background check but is there anything else I should know?

What would happen if it got involed in a crime? Would I take the hit? How does that work?

As long as they weren't purchased as pistol lowers it's just swap money for lowers. Same as long guns in PA.

The buyer has to be a legal gun owner. If they are strangers the best thing to do with a FTF sale is check each others LTCF. Not 100% air tight but it's something other than "here's your money" and "here's your gun strange person"

You can do a bill of sale type thing if you want to keep it for your records. You both sign it and either make copies or take a pic with cell phone.

I'm no expert but that is everything I can think of right now.

+1 on asking to see LTCF. Not necessary, but I've usually done that as a way of verifying they aren't a prohibited person...at least verifying they weren't a prohibited person when their LTCF was issued. Only so much you can do.

I've always done bill of sales as well, but again, not necessary.

asking for an LTC is pretty lame. What if the guy wants a rifle for home defense and/or taking to the range on weekends and never wants to carry a sidearm concealed so never got an LTC. Does that mean the 2nd doesn't protect him? As part of a long gun he doesn't need a background check or an LTC. If he buys it from you and uses it in a crime the feds will come knocking. All you need to do is tell the truth, you sold it to a guy and if they ask you to ID the guy, co-operate. If you want to cover your ass, tell the prospective buyers you will only do a transfer sale through an FFL. If they do it, you are covered. If they refuse, walk away.

I disagree.  If the requirements as a seller are to validate that (1) the buyer is a resident of the same state, and (2) not a prohibited person, asking them to flash their valid PA LTCF takes care of both.  Just making it a requirement weeds out a lot of the garbage.  I can't tell you how many times I've had potential buyers approach me with shady shit.  Making LTCF a requirement is like a filter to take out 87% of the stupid.

Now, Bill of Sale on the other hand... that's lame.  

mmmm...maybe... but a drivers license would let ya know if the buyer is a resident. Since the OP is talking about someone he works with, he probably knows if the guy is a bad egg or not but in general an LTC sort of helps weed out the folks that aren't actual felons... maybe. But the thing I'm saying is the guy shouldn't have to have a note from the ruling class to own a firearm and be protected by the 2nd Amendment. And in fact, in this case, he doesn't really need a note from the ruling class to own a firearm and be protected by the 2nd Amendment.

To the OP, if you like your working buddy and trust him enough, it's just a sale of a long gun.