For #4 -- RoboSats ... even taking an existing order from a Seller requires you to have sats -- for the taker bond. The amount of sats is a small amount ... like 3% of the trade amount, but a buyer without any sats yet cannot do any trade, buy or sell, on RoboSats.

The RoboSats Telegram shows traders not being able to use the default ("legacy") hosted channel on SBW to pay the RoboSats bond. Not sure if that problem occurs or not with the other hosted channel providers that you listed, but wanted to point that out.