i made the switch to DD only for regular work about 4 years ago.
it is a job to get poeple switched over, but the payoff is well worth it.
new customers of ours need to setup the DD before we will book them in. practically everyone is either happy to do so, or some will think about it, then just do it. its very rare for someone to refuse and some of those are people who want one off cleans
its so simple to raise prices, check a payment query, you get paid ontime for 99.9% of your jobs.
we dont accept any other payment now (except 5 customers from our start who still pay us by cheque)