For couples planning a wedding, the months leading up to the day are exciting, but also stressful, especially when dealing with complicated family dynamics that come into play when it comes to finances.

“Most couples are paying for part if not half of the wedding, and then parents are paying for some fraction of that wedding,” says Meg Keene, founder of wedding planning website, A Practical Wedding. “Weddings are not bought, everybody gets to be invested, but there’s a real issue with parents having expectations that don’t match with financial reality.”

The average wedding costs $33,391 according to the Knot, and deciding who can and will contribute can lead to some sticky situations. Keene offers her tips for avoiding financial drama with your family.

TIP: Prioritize early on

Keene says it’s crucial to avoid problems down the line by meeting with each set of family members and finding out what their priorities are for your wedding day.

“I think it's really important to sit down when you get engaged and ask what their top three priorities are for your wedding, and if anything is non-negotiable,” she says. “Then you have to draw the boundary and say, ‘we are the ones who have to figure out how this works’ and you’ll do your best.”

By listening and taking into account what’s important to your family, it will be easier to decide how your money will be spent, whether you’re the ones paying or someone else is, Keene says.

TIP: Set financial boundaries

When it comes time to work out the details of who will be contributing, you need to set expectations about who is calling the shots, Keene says.

“When people say, I'm going to pay for everything, you need say, ‘if you do that, it's still going to be up to my partner and [me] to decide,’” she says. “Then ask, ‘Does that work for you?’ which gives people a chance step back out.”

While it may seem appealing to accept money for your wedding, Keene says you need to know what that will entail.

“You’re going to have to make a decision: are you will to take money with strings, or would you rather have a [less expensive] wedding with no strings?”

TIP: Learn to say no

Keene says it gets complicated when people have demands for what they want but then don’t offer to pay or have the money needed to contribute. It often just comes down to helping your family understand how much their demands will cost.

“They might say, it has to be a seated dinner with waiters, and you say, that’s not going to happen because of the cost,” she says. “You need to say, if this is important to you, this is what it will cost.”