Could anyone help me out by giving me some more ideas in how I can prepare my new condo for visits from my cousin?

My husband and I are buying a duplex Chicago-style condo. We bought the first floor & garden unit for easier accessiblity for her. We are like sisters, but she doesn't visit too often, and has to fly in from San Fran - maybe once a year. I am having a temporary ramp built so when she does come I can have it out for her. The builder is being very cool with letting us modify his design, make upgrades, etc.

My main question for anyone who can shed some light is, what dimensions should the bathroom be? She told me it is easiest for her to take a shower in a "shower" not in a bathtub, because if not, she will need to bring much more equipment to attach to a bathtub. So we asked our developer to modify our master-bathroom into a shower instead of a jacuzzi tub. She doesn't seem to know much about the exact dimensions she needs, so I'm hoping someone in this community can help me out.

Also, any other ideas you may have about the home that would make her life easier would be very appreciated!

Thanks in advance.