If each spiders paid 0.1% of rent and utilities how many spiders would you let in?
The kind of spiders is based on the species you most commonly find in your living space now. Each spider will have its own personality but, will largely behave a normal spiders in a environment they feel safe, with that said if for example you let it get to cold there will do something about it.
If they pay part of the mortgage and utilities and taxes 0.1% is actually quite a bit.
So the most common spider inside is nothing to really be afraid about, mostly they're so tiny they'll be the size of ants. I probably wouldn't even really notice 10 of them.
Now if you would've said the largest spider to frequent your house I would say 0. Get those big ass hairy longleg fast fuckers as far away from me as possible. Eratigena atrica is what they call it.
I probably already have a thousand spiders in my house anyway so I'll gladly take the cash for being their roommate. Maybe 999 so they don't get pissed that I'm freeloading.