The bathroom needs to be for the toilet and showering. Some sort of alarm timer so people keep showers to 5mins. All other getting ready needs to be done in bedrooms.
Get a mirror with a drawer/tray on the bottom for your skincare and makeup, then it can go on any table and be moved around easily.
IKEA is great for furniture that doubles as storage, all furniture needs to be this in a space so small.
Use the walls, go up instead of out - shelves, cube units, Really Useful Boxes stack well.
Price the replacement cost of anything you're thinking of taking to storage and price the cost of a year's storage, then decide if it's really worth keeping the stuff. Your money might be better spent on more suitable furniture for now than a storage unit to keep things for later.
Get strict with laundry, if it's only been worn to go out in for 2hrs it's not dirty and doesn't need to go in the wash. You're maybe not going to have room for a clothes airer or a tumble drier. So you'll need a washer dryer (and an ironing board - they put creases in, unlike a normal dryer) unless you've got an outside space to dry things. Otherwise you'll have washing draped on curtain rails and radiators constantly which makes the place feel messy and costs a bomb in heating to get it dry (you need to keep opening the windows to let the damp air out or you'll have mould.)
As PP says, you need to do your living outside the home now so as not to get under each others feet. Home is just for cooking, washing, laundry, sleeping and storing a minimum of stuff. It's totally doable though.