Payment terms define when an invoice is actually due: due on receipt (now), net 15 / net 30 (within 15 or 30 days), or the informal 'whenever I see them next' — which is a term too, just a terrible one. The terms you set shape your cash flow more than most pricing decisions.
Where net 30 comes from and where it belongs. Net terms are a business-to-business convention — commercial properties, HOAs, and municipal contracts often require them because their accounts-payable departments batch payments. If you take commercial work, net 30 is the cost of entry; price it in, because you're effectively extending a month of free credit.
Residential is a different animal. A homeowner paying for a mow is a consumer transaction, and consumer expectations are shaped by everything else they buy: pay now, card on file, automatic. There's no reason a residential mow should carry net-30 terms except habit. Every day of float is collection risk you're donating — operators who moved to charge-on-completion with a card on file effectively run net-zero terms, and their receivables aging is a blank page.
Setting terms without awkwardness. State them at the estimate stage, not at the first late invoice: 'we bill when the visit's done — most customers keep a card on file so it's automatic.' For check-and-cash holdouts, due-on-receipt with a friendly automatic reminder at day 7 keeps things moving without a confrontation.
In Grassr, the default is the strongest terms there are: the invoice generates at completion and the saved card is charged on the spot; cash and check customers get due-on-receipt invoices with reminders. More mechanics under lawn care invoicing and recurring billing.