Pay Dirt is Slate’s money advice column. Have a question? Send it to Kristin and Ilyce here. (It’s anonymous!)

Dear Pay Dirt, 

I’m a high school student and my mom wants to do something incredibly stupid. My prom is coming up, and my mom wants to buy me a dress only to have me wear it to the prom and then return it! Please give me some help in talking her out of this!

—Shocked Senior

Dear Shocked,

Your concern is totally valid—there are so many reasons this sounds like a bad idea. For one, wearing a dress you know you’ll have to return will stress you out the whole night. What if you spill something on it? Or sweat a little too much? What if the tag gets mangled while you’re on the dance floor? No one wants to worry about any of that on prom night. There’s also the little fact that what your mother is suggesting is essentially stealing. If you’re being coerced into doing something you feel is unethical, that’s no way to spend prom night, either.

But I’m guessing the reason your mom suggested it is because she wants you to have something special but can’t afford it right now. That matters. When you attempt to talk her out of this, it will help your case to acknowledge the fact that she wants you to have a nice dress.

Surely there are better solutions, though,

Before you talk to your mom, get clear about what exactly bothers you about the situation. For the sake of having a productive conversation, pick the thing that bothers you most to talk to your mom about. Focus the conversation on how it makes you feel, rather than the fact that you think it’s a stupid idea.

For example, if your main issue is an ethical one, you  might say  something like, “I’m excited about prom and I really appreciate you helping me pick out a dress. But I feel morally uncomfortable with wearing an item and then returning it. Would it be possible for us to buy something secondhand? What do you think?”

I’d also offer some alternative ideas, like renting a dress online or buying something secondhand. Chances are, there’s a better solution, and you won’t have your prom memories tainted with an ethically dubious situation or a stressful dress.

Dear Pay Dirt,

My husband and I are currently housing a friend from college (we’ll call her “Mary”) while she gets back on her feet. Mary had to leave a toxic roommate situation in a hurry; they’d been “family” for 25 years, but sadly, he is an alcoholic whose behavior has gotten worse over time. Although we knew Mary couldn’t contribute to the rent when we invited her to come stay, (she has a number of disabilities that have prevented her from any meaningful employment for almost six years), she said she’d be more than happy to watch our two children so we could get an occasional date night, and she would work her hardest to finalize the official diagnosis of her myriad of ailments, apply for SSDI, and as soon as that approval came through, take her payouts and get out on her own.

Mary gave me a reasonable sounding timeline (she’d “probably” be out by fall), and so we opened up our guest room to her and her two cats. That was seven months ago.

We learned very soon after her arrival that Mary’s situation was much worse than she’d let on. Her physical disabilities are so bad that she spends most of her days in bed, and her patience for my children, particularly my 9-year-old son, is almost non-existent. She has been openly rude to me and implied that I should be more available to her in case she has a fall (apparently this is a possibility with one of her ailments). It has also taken her much longer than anticipated to get her SSDI application submitted, and the timeline for that approval is now sometime in January.

Although I was more than happy to provide our guest room, I did not sign on to be a caretaker, and I certainly don’t think it’s okay for her to treat us with any level of disdain when we’re doing her a pretty major favor. My husband has tried giving her a deadline of the end of the month, but realistically, we know this process won’t be done by then. We are all miserable and need her gone as soon as possible. But we don’t have anywhere else for her to turn that will both allow her to keep her cats with her and will not require some kind of payment, which she doesn’t have the means to pay. She’s estranged from most of her family, except for a cousin who lives halfway across the country.

What recourse do I have? How do you get a rude, disabled squatter out of your house who has no job and nowhere else to go? We’ve tried so hard to be hospitable but this situation is no longer sustainable.

—No Good Deed Goes Unpunished

Michelle Herman Read More

Dear No Good Deed,

I get your frustration. You’ve been incredibly generous, and now that generosity has left you feeling resentful. It truly sounds like your friend is going through a difficult time, but you’ve done what you can, she’s responding with hostility, and now it’s time for something to change.

At this point, it’s important that you and your husband communicate a firm timeline for her to leave. You should, of course, both be on the same page about this, and the good news is that it sounds like you already are. This might sound something like, “Mary, we understand that you’re in a tough spot, but this living situation is no longer working for our family. We need you to find alternate housing by [specific date].” You can offer to help her out in limited ways, sure. But she should know that you won’t be able to continue hosting her after that point. You want to be compassionate, but don’t leave the date open to negotiation.

This Content is Available for Slate Plus members only My Son And His Cousin Look Exactly Alike. My Wife Can Never Know Why. I Refuse to Do Free Work for My Family. They’re All Having a Meltdown. I Made a Simple Request of My Friends With Kids. Well, Now They’re Outraged. Help! My Fiancé Took a DNA Test. Now I’m Considering Calling Off the Wedding.

Part of the challenge here is also a logistical one. It’s okay to offer to help her out with next steps, but if you do, set some firm boundaries. For example, maybe you help her research local nonprofits or transitional housing programs, or look into disability rights groups that can help with her SSDI application, or even foster her cats if they’re keeping her from finding housing. If she has a cousin who’s still in contact, you could also consider encouraging her to reach out. Just make sure she knows you’re pointing her toward resources, not taking the responsibility of solving the whole situation.

You might also consider consulting a landlord attorney or your local housing authority. Depending on your state, someone who’s lived in your home for this long, even rent-free, might have tenant rights, and if she refuses to leave, you may need to issue formal notice or even pursue legal eviction. It sounds harsh, I know, but if she’s being hostile, it might be wise to at least know where you stand legally.

Ultimately, you and your children deserve a peaceful home. If Mary is treating you or your son with hostility, that crosses a line. You’ve done a lot and, at this point, drawing a boundary is a must.

—Kristin

More Money Advice From Slate

My parents had three children: my sister, “Valerie,” then my brother, “Jack,” then I came along as a surprise when Valerie was 15 and Jack was 12. We all turned into very progressive liberals, which was a constant disappointment to our very conservative parents. But, Jack, whom they could never accept as bisexual, got the worst of it. They were fine as long as he dated women, but when he married a man, they cut him off and refused to even speak of him. They cut him out of the will , too, and my sister and I are at an impasse.

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