Why do a down payment on bigger jobs?

[evo]

Reading all of the responses is taking a deposit based on demographics, advertising methods, and location?
A solid 90 some % of my work flow is all word of mouth somebody knows somebody who happens to be friends of mine kind of thing. So I've been insulated from some of the nonpayment drama for the most part. And If they don't pay I have my wife call, she use to be in property management and over saw 600 units at one time. Merciless! But I get a check with a letter of apology. True story: I had a custy dodge me for 4 months, my wife called I had a check in 24 hours.

My business is much the same way. It use to be 100% words of mouth and then just one listing. I do keep that one listing and a google ad. Both is don’t view as hard advertising, just keeping my name and number in mind and reach. I’ve only had two non payment issues which eventually resolved.
im also 95% signed contracts for new clients, and existing fixed price clients. Some new, and some return is a handshake or ‘just come over and do it I don’t want to waste your time with a quote’. Those are the gold clients, so non payment is never a issue.
Like reach I don’t get many cancellations, but it does sound like a bit more, maybe 4-6 a year. Half of those I don’t even worry about because I understand life happens and changes occur. The other half are just assholes.
I’m thinking of deposits more along the lines of a higher level of professionalism, a little for cash flow, and the remainder for cancellation mitigation. It’s not from lack of work, I’m deep into September at the moment. It’s mostly waiting for shit to get mailed or checks to clear. I’ve noticed a huge uptick of new clients almost begging to give me a deposit so it’s got my gears going again