Look inside the receiver, along the rails that the bolt head rollers contact. Check for indentations to the inside of the rails, either near the trunion or the real of the receiver. Check the barrel for pitting, and worse, a bulge. Bolt gap can be addressed, usually by changing rollers to a larger size. Trigger group and buttstock should go on and off easily, and hopefully you won't need to hammer out the buttstock pins, they should install and be removed by the fingers, although may be tight.
But that ISN"T a good indicator of condition. They may have replaced to rollers.
Like buying a used car? Condition is everything! Be careful if the gun looks too nice, it may have been refinished. (That will make a beater, look good)
Best thing to do is ask questions and find out as much as you can on the history of that weapon. Check out the bore. It's hard to determine if the gun was at some point a Full auto and got shot to hell!!
The integrity of the seller will be your best indicator. There are great deals here on the forum that pop up from upstanding member here. Don't rush into buying a gun! Learn all that you can and be patient.
You guys may have missed the most important thing. PRICE. If the gun is $1,200 you have plenty of room to restore it worse case. If the Seller is looking for 3k it better be LNIB with the original box, and a story to match why it was not shot in 30 years.
The current market seems to be selling (key point here, not advertising you own the gun) 91s around $1,900 to $2,300 as described above with matching codes and such. Good Luck and do your homework, and never rush in unless the seller wants $1,000.
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