Tested a fixed-scope offer at a higher price to see if cash flow smooths out

Before I add a second offer I want to know whether my cash problem is the retainer model or the deals themselves. So this month I quoted three new clients a fixed-scope package at roughly 40% above my usual monthly rate, paid 50% upfront. One said yes immediately, which I did not expect. Two went quiet, but one of those came back asking to split it into monthly payments.