[UT] How should me and my roommates split rent?

I am dating someone and am moving in with them. her 2 roommates are trying to make us pay 700 a month while they pay 400 a month. This seems to be very high considering we have the basement that has no doors and the laundry room shares a wall with our bed. I also pay for all the toiletries and the food I buy usually gets shared. I believe a 40/30/30 split should be fair but I need to confront the roommates first so I’d like some information from Reddit.