we have some cash sales - standalone and ones from SO's with no Cogs impact; the items have Cogs account selected. Any suggestions?

A standalone Cash Sale assumes that's the only transaction of the whole interaction, so it's going to affect inventory and COGS will be hit there. If you start with a SO and use a Cash Sale as payment though, the system assumes you're going to have a fulfillment and the COGS info will be attached to that record.

@RJMNS totally, but standalone cash sales are missing COGS impact too

do the items have "Can be Received/Fulfilled" checked and/or are they inventory item types?

Also, in my experience if you fulfill it without location quantity on hand or without location inventory value, there's also no GL impact

@RJMNS thanks @Luis what you suggested was spot on. it fixed the issue.