For a little bit of background information before I get into the question:
My cousin is marrying his long-time girlfriend now fiancee. We are all excited!
She asked me to be her bridesmaid - I happily obliged.
I am out of town and am not available for hosting bridal showers.
I've already gotten my bridesmaid dress and have gotten her a gift for an upcoming shower.

can't wait!
But one thing is bothering me:
Her maid of honor is planning a 4 day beach getaway Memorial Day weekend.
I've been asked if I am available for those days, and I would be. I've asked how much this would be so I can know if I can afford to go on this weekend.
I haven't received a response in weeks after inquiring one other time. I do not know the MOH, so I'm not sure how to proceed.
There are 3 total bridesmaids (including MOH).
I love my future in law but am not sure I want to pay for a 4 day bachelorette getaway. I'm definitely down with paying for a night on the town and things like that, but I don't have hundreds of dollars to put down toward this. How can I politely decline/address money? The other bridesmaid is not being included in the planning either, and we can't get much out of her. We will be seeing her in person this weekend, however.
I am doing an internship where I get no income, so I'm not exactly in a great financial spot right now. I have savings but want to use them toward my own wedding/future living expenses.

This is my first post on The Knot, so I hope I did okay!