Most cost-effective way would be to browse for an old used one on ebay, should be like $500-1k if you’re in the US.
Like the other poster said, fill it with products from Costco, the only issue is packaging things like single use detergent. You’d probably want a box or something for pods or powder so they don’t get damaged.
You could also use these: https://www.amazon.com/...
Looks like they’re a bit over $1 each, so sell them for $1.50 or $2 in the machine. Don’t confuse them with the sink packets which aren’t for machines.
The just sell the machines, or lease them. A lot of smaller operators buy in bulk from Costco and use that to stock the machine.
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