This auction had an M79 and 3 M2s
https://www.rockislandauction.com/catalog/4090/class-iii/
10.5K M79: https://www.rockislandauction.com/detail/4090/454/varo-m79-blooper-grenade-launcher-class-iiinfa
64.6K Real C&R M2: https://www.rockislandauction.com/detail/4090/477/us-springfield-m2ac-class-iiinfa-cr-fully-transferable
47K Real C&R M2 w/issues: https://www.rockislandauction.com/detail/4090/3502/us-kelseyhayes-m2-class-iiinfa-cr-fully-transferable-mg
32K Sideplate M2: https://www.rockislandauction.com/detail/4090/1495/berton-r-miller-m2-class-iiinfa-fully-transferable
IMHO, the M79 sold above mkt and the sideplate M2 sold below mkt
Re: M2 accessories - Usually you can maximize value selling by accessories separately from gun, but for an M2, less easy to sell and most likely
will get help the gun for a higher price to a potential buyer... Factory ammo certainly has value separately, but 50ammo can be difficult to ship...
Re: sideplate gun differences - IMHO, there is much difference between them - builder & config prob impacts more and anything else.