(AP) — Customers who pay late or don’t ever pay are a problem for any company, but particularly for small business owners who lose time and money pursuing the money they’re owed. Some tips to help owners be sure they get paid:

— Use written contracts that spell out payment terms. Contracts serve two major purposes, putting customers on notice about when and how they’re supposed to pay. And if an owner needs to take a non-payer to court, the contract will be evidence that the customer agreed to the terms, says Michael Eckstein, an accountant based in Huntington, New York.

— Do some due diligence on customers. Before agreeing to work with or sell to a customer, doing a credit check or researching them online can help a business to avoid payment problems. It’s particularly important when large amounts of money are at stake.

— Get a deposit or payment up front. Becky Beach, a website designer in Arlington, Texas, asks clients for half her fee before she starts work. She formulated that policy after having to chase after customers — even visiting them in person to collect late payments.

— If a customer doesn’t pay, an owner should follow up in a timely manner. Some owners send emails seven days after payment was due. If payment still isn’t made, Eckstein recommends following up once a week; he notes that there are apps and software programs that make sending these reminders easier.

— If an owner wants to keep a customer who’s a late payer, a mix of firmness and friendliness will help.

— Be ready to negotiate if that’s the best way to get at least partial payment. Marsha Kelly, a consultant who has also had a career as a manufacturer, worked out payment plans with some customers, and she was also willing to take gift certificates to restaurants and hotels who were her customers.

— Use collection agencies and lawsuits as a last resort. Both alternatives carry expenses that will reduce the amount of money an owner can collect, sometimes by half or more.