When freelancing is your primary source of income, you have to be meticulous and organized about keeping your books, according to Jon Younger, the founder of the Agile Talent Collaborative, a nonprofit research organization and the coauthor of Agile Talent. “If you’re not disciplined and rigorous about getting paid, you will not succeed?！?And yet, even if you do everything right, clients can still be frustratingly late with their payments. Over 70% of freelancers have trouble getting paid at some point in their careers, according to research by the Freelancers Union, the nonprofit group that promotes the interests of independent workers. “When you’re on your own freelancing for a big company, there is a fundamental power imbalance,” says Caitlin Pearce, director of advocacy and member engagement there. So if your paycheck doesn’t arrive on time, “You think, ‘What did I do wrong?’” Here are some strategies to help you run the “billing department” of your freelance business.

The best way to ensure you get paid in a timely manner is to work only for reputable, well-funded companies that treat freelancers with dignity and respect. This requires due diligence, Younger says. “Before you respond to a request or knock on a door in a marketing capacity, you need to establish that the company can pay you and will pay you,” he says. Pearce recommends talking to other freelancers who’ve worked for the organization about their experiences. Inquire with the company’s full-time workers, too. “Ask about the corporate culture,” she says. “ How it treats employees is a good indicator of how it treats freelancers.” The bottom line: Don’t work with clients who have a bad reputation.

Next, you need to consider how you will bill your clients. There are many ways to go about it, and “there are pros and cons for each,” Younger says. Choosing to be a “truly independent worker” and handling all the invoices on your own requires more bookkeeping — and potentially more headaches — but all profits go to you. (Thankfully, there are numerous tools and apps that automate the process) On the other hand, being part of an “online talent platform that connects buyers and sellers” — means less legwork and less paperwork because “they collect the money for you”; however, these platforms also take a cut of your earnings. Regardless of what you choose, it’s smart to seek out the advice of an accountant from time to time, Pearce says. “Most freelancers do not use accountants for bookkeeping” but instead as “periodic consultants.” They “help you prepare taxes, make sure your costs are under control, and ensure your business is structured properly.”

Before you start working on an assignment, you need a contract that lays out the scope of the project, the payment terms, and the expectations for both sides. “Don’t believe in a handshake,” Younger says. Informal agreements are the source of almost every payment problem, so be sure “to get everything in writing.” For small projects an email chain will often suffice, but for longer engagements “it is worth working with a lawyer,” Pearce says. Most freelancers have a standard template contract that they alter for different clients. “When you can, work with your own contract,” she says. “You know what’s in it, and it has terms you can live with and negotiate from.” The Freelancers Union has several templates on its website, as well as an app that connects freelancers with attorneys who represent independent workers.

It’s also important to talk with your client about its “payment schedules and policies in advance” of starting any work, Younger says. Find out how long it typically takes to process invoices, which days of the week it cuts checks, and how it pays its contract workers. This information helps you better manage your monthly cash flow. Pearce recommends you “try to get as much money up front” as possible. “A deposit of 30%–50% of your estimated fee is acceptable in many industries,” she says. Another tip: “Make sure you have the name and contact details of the person in finance with whom you’ll be dealing with,” Pearce says. This way, if there are delays, you have someone to call.

Regardless of your client’s payment terms, Younger recommends establishing your own billing cycle that’s frequent and predictable. “Bill on a weekly basis or every time you finish a bit of work,” he says. Billing often is “a signal that you consider your time valuable.” For longer-term projects, Pearce suggests invoicing at predetermined “milestones along the way” so that you are guaranteed “payment at certain points over time.” Milestone payments not only help you manage your cash flow, they are “also a tool for communication”. She says, “They make sure you and your client are both aligned and satisfied.” Whatever you do, don’t agree to terms that involve your getting paid only upon the full delivery of the work. “You don’t want to work for three months on a project only to have the client say, ‘I hate it. And I will only pay you for 50%.’”

Earning your living as a freelancer requires that you “treat yourself like a business,” Pearce says. Don’t do slapdash work, don’t “forget” to invoice, and don’t be careless in your communications. “Getting paid is contingent on the quality of your work and the quality of your relationship with your client,” Younger says. On a related note, don’t work for free. “A lot of companies are fishing around these days for free work on the assumption that your working for them will help you more than it realistically will,” he says. Remember this any time you’re “invited” to give a free webinar or moderate a panel gratis. “Talk plainly and in businesslike terms” about your fee. “Establish the value of your work.”

If your client is ever late with a payment, “you have to be vigilant about following up,” Pearce says. “If you’re vigilant on your end, it sets expectations on theirs.” If you’re following up and no one is responsive, “escalate to a phone call or go to the office in person,” she says. It’s much easier to ignore an email than it is to ignore a human. Be persistent about seeking payment, Younger advises. “Don’t give up,” he says. “Work your way up the food chain and take it to the top” of the executive leadership if you need to.

If you’ve tried everything and the client is still not paying, it might make sense to engage an attorney. It’s not a straightforward decision, however. “Mostly it’s a cost-benefit analysis” that involves calculating the amount that’s owed you, your odds of success, and the hassle of hiring — and paying for — a lawyer, Pearce says. A new, first-of-its-kind law in New York City gives freelancers a ray of hope. The law stipulates that for jobs paying $800 or more, freelancers must be paid either by a specified date or within 30 days of completion. The other big component of the law provides recourse for instances in which clients fail to pay. “If it goes to court, the law mandates double damages and attorney fees be awarded if the judge rules in the freelancer’s favor,” Pearce says. She adds that the Freelancers Union is “working on getting the law passed nationally.” At the very least, report your former client to the Better Business Bureau.

Your research. Find out how well-funded your client is and, to the extent possible, check if there are any financial red flags.

Bill on a regular basis, and for longer projects ask for milestone payments; they help you manage your cash flow and ensure you and the client are aligned.

Consider pursuing a settlement in court if your client fails to pay you.

Work informally. You need a good contract that lays out the scope of the project and the payment terms and ensures that expectations are clear on both sides.

Be lackadaisical about following up with your client about a late payment. If the client does not respond to emails, visit the office in person if possible.

Michael Lopez, a freelance copywriter specializing in the health and wellness sector, knows all too well what it’s like to get stiffed by a client.

Last year he agreed to do web copy overhaul for a drug rehabilitation company that had a network of treatment centers. He had done small jobs for this client in the past, but the new assignment was much bigger. This project was slated to last two months, and it represented “a good chunk of change” for Michael.

He finished the job and submitted an invoice. He didn’t hear back from the company, so a week later he followed up with an email. No response. After two weeks, he followed up by phone. Still no response. “After four weeks I followed up with another call and email and was told that they were working on payment and reviewing the work,” Michael says. “[They also told me] that they didn’t feel they would use the deliverables, so they were not sure if a full payment was fair.”

He was surprised, angry, and annoyed. “I went through all the stages of grief,” he says. “I eventually ended up feeling sad and disappointed in myself. Yes, they were in the wrong, but there were a lot of things I did wrong as well.” For one, he worked without a contract. “A contract was something that I knew I needed, but I hadn’t been able to put one together,” he says.