No to a group.
Yes for business to business.
Yep, it must be treated as cash per irs.
Yes, we do a large amount of in kind donation work. In fact, we do either that our donations of product, no cash, as policy.
A group called "we trade" approached us on this once. They were basically making up their own currency, taking a percent and, get this, brokering screen printing work. Yeah, they left the list of printers in the group hidden and controlled where the jobs went when a member asked for printing services.
Avoid these groups, they offer nothing you cannot arrange business to business.