Interesting. The Model 29 is the rarest of the Remington pump shotguns. It was only made for a little over 3 years, basically the Great Depression and competition from vastly more popular competitor's guns killed it off.
The pros of this shotgun is there are no pros, other than relative rarity to the Remington collector. In this case, however, rarity does not really translate into big $. Collectors are usually interested in guns in better condition than this one sounds.
If it were a solid, restorable gun with no rust damage or serious metal flaws, it might be worth from $100 up to $200.
However you said this is at a pawn shop, so if they are anything like the pawn shops around here they probably want $300-400 for it. Am I right?
Grouse