GI M1 carbine collection rough value

Nowhere near enough info for an estimate. Could be anywhere from $6000 to $50000. Most likely in the 10-15000 range, but that is just a WAG.

Each one really needs to be taken on its own merits. For example an original late Winchester is worth more than a mixmaster rebuild Rock-ola. Condition, import marks, fake parts factor in. Maybe one of the mixmasters has a rare part that makes it worth more. You get the idea.
On a real basic level there's not many decent USGI carbines selling for less than 1100-1200 these days.

Rockolas and Winchesters are pretty much neck and neck on auction sites, but there were far less Roclolas manufactured so they definitely bring a premium price.  In today's market a $1000 USGI carbine is just about obsolete, so it has definitely become a sellers market.  Like others have said, there are collectors out there looking for the originality of parts and/or manufacture dates which could inflate the real value of a certain carbine.  It is quite apparent that the original owner of those carbines was trying to have a complete set of all the WWII USGI carbines.  That in itself puts a premium price on any collection.  As for what they are worth?.....basically what someone is willing to pay and that could be a very healthy amount.

Thanks guys. I have been taking them apart and inventorying the main parts. Not done yet, but a couple highlights, the Saginaw appears to be all original except for the stock. One of the Winchesters is a spring tube receiver. Only the Underwood has import markings. The IBM is in good condition. Has a rock ola trigger housing. They are all in pretty good condition. One Winchester has a Winchester stock also. I can post more information when I get them all done.

Interesting auction. Good exterior pictures for the most part. Some interesting rifles in there, e.g. 314.

I purchased Lot 286 - The inland “X” suffix carbine.  Just delivered on Friday and still need to take it apart and photograph it.