I received notice of this 394-item auction.  It contains some high value Cox products as well as some older engines that might be wanted by collectors.

https://hibid.com/michigan/lot/210358568/o-s--max-10-engine-wooden-car-and-syncro-bee-motor?ref=catalog

Note: there is a 20% "buyers premium" which I assume is a commission added to winning price.  That would be a dealer-breaker for me, unless I really needed a thing.

Two engine medium bomber.  Currently $40 + 20%.

https://hibid.com/michigan/lot/210358571/b-25-mitchell-gas-double-engine-tether-plane?ref=catalog