Prefer you ask? SHOTGUN...lol
I use Quick books and they offer an Bank to Bank payment option for .50 per transaction. Is that a big hit? I think not in comparison to each transaction with a credit card.
This is the first season we attempted this..Roughly 40% of our customers jumped on it...so email is essential for us....probably for any business. We did have a few people who could not follow the 3 step set up, but Intuit helped them get it set up.
Literally have customers that are anal about paying & others who act like they do not check their email. But to ask for a month in advance for anything would be completely out of the question.
Although this past spring I offered current customers the same weekly lawn mowing rate as last season, for early payment. I made it affordable for them to basically send a down payment on the first month of lawn mowing or service we would provide them and it worked like a charm. Plus it gave us the cash on hand for spring start up costs....fuel, belts, oil, etc.
Hope this helps...good luck