We have decided we definitely need the large ones. Mike's Woodshop has trolleys that take 18 trays and ones that take 12 trays (large sized). The 12 tray trolley is $240 and the 18 is $325 - the total is $565. The trays are $6.50 each. Total - $195 for 30. Tote trolley and trays come to $760.
So altogether now we have spent about $3100.
Maybe Mike's Woodshop would make us a custom trolley for 30 or 32 trays. We will email them to find out.
Next job - low kneeling tables / pods and chairs / sofas.