They have been discussed on the other snowblower forum a few times..
Pete has a photo of one here:
Pete's Vintage Snowblower Showcase
The Homco units are most often seen as early Sears Craftsman snowblowers..(built by Homco, badged for Craftsman)
value? hard to say..on the one hand, they are quite rare, which would suggest a high value..but on the other hand, no one cares!
which suggests a low value..
If I saw one for sale locally, and it worked, I would pay up to $50 for it, but no more..just to have it for the novelty..its a pretty primitive machine, and probably not a top performer..non running but basically complete, perhaps fixable, I would offer $20...but like anything else, value is only what someone is willing to pay..if someone decides they want to pay $100 for it, then that's what its worth...but IMO its not worth $100.
(assuming its that "basic" Homco like the one on Pete's Gilson page)..I dont know what a "snow mule" is, or if its something different..I have only ever seen the one style of Homco machine..not much is known about the Homco units..if you buy it, please post photos!