FM Cloud in combination with a 5-user FLT will cost around $120 per month (depending on the type of virtual machine you choose). That includes the hosting (unlimited # of files), FMS and 5 licenses for any mix of FMP, FMGo and WebDirect.
$120 per month... if that is not affordable for a small business then I don't know what is. And it removes the immediate need for a thin client since you get everything as one package deal.
I get your point about rationality etc. But I would be looking for a minimum of rationality; I don't want to be in a position to have to defend the bills for my work the same way. That's going to be more than $120 per month.