Event space rentals for parties

I was wondering if anyone could point me in the right direction regarding how to legally rent out a space for just a single day to host a party...

What kind of space?
What kind of party?
How many people?
Where at?

Back when I turned 30, I was hunting for a spot for an overnight stay for 18 people—somewhere near Cleveland

I stuck to a radius of 19 miles around Cleveland (it’s not great for the designated drivers to be cruising for too long after a night of heavy drinking) and my only non-negotiables were a pool or a huge jacuzzi and enough beds for all 18 of us. Honestly, I thought this would be a breeze—money wasn't even a massive issue—but man, it turned out to be a total nightmare. Every single villa or rental house in California or around Cleveland requires at least a 4-day stay (and even then, that's rare; usually it's a 7-day minimum), and all I needed was one Saturday night.
I scoured all of Expedia, Airbnb, and every random private site I could dig up online. I barely found 10 places that fit the bill—some explicitly said "no parties," so I skipped them, and three I actually booked through Expedia ended up calling me a day or two later. Once they asked what the occasion was (I was upfront about it being a birthday bash), they basically politely asked me to cancel and refunded my money.
After that failed hunt, with only a few days left until my birthday, I had to compromise. I booked a complex of 2 houses in Boise (there are 3 houses total in the complex) that have a shared indoor pool and sauna for $400/night per house—so $800 total for one night. It wasn't perfect location-wise or price-wise, but I couldn't find anything better.

Basically, you usually have to know someone to snag spots like that, but unfortunately, I didn't have any connections who could pull strings for a group of 18 (you can find stuff for 8 to 12 people, but anything over that is a massive headache).

I was just wondering about the best way to handle renting out a space... whether I actually need to set up an LLC for it, or if I can just manage the taxes on my own and keep things simple

You don't even need that.

I can't speak to how things would shake out on a daily rental basis, but I can certainly walk you through our monthly setup.
My brother runs his own business, and the headquarters is actually located right in our family home—which, for the record, my father and I each own 50% of. We drew up a formal lease agreement, had everything notarized, and filed all the necessary paperwork with the IRS.
Every month, my brother pays a rent of $333 while I end up paying roughly $30 in taxes.