I have a contractor and have consulted an architect. However, Houzz has offered many good suggestions in the past on projects. Before making major decisions, I want to look at several options for my project. You don’t have to chime in.

It would be better if you hired someone who is knowledgeable with codes for ADA bathrooms. They can design what you need.

What you've posted isn't enough for someone to draw up plans for you. Please hire a contractor who can pull permits and do this for you.

Yes, I have. The 70’s ranch conversion and separating master bedroom/ bath to other side of house is the biggest hurdle I’m facing. Keeping all three sliders is my other obstacle.

I can't add to the design, but can give a tiny bit of advice. it would be worth checking if there is a tax deduction for those changes in your area before you start as well, and if so, what documentation you need. I missed out on 5 grand when I installed an accessible bathroom, because I didn't have adequate paperwork to show the price difference.

If you'd like some input into your ideas, you need to post a better plan. this one is too fuzzy and there are no room dimensions or walls, doors, windows. I know many good ideas have come from brainstorming projects. Post a better plan and you might get some feedback on the project.

In order to do what you want you need an architect, a good contractor and the help of ADA compliant rules. Your floor plan is too fuzzy to read and making a house wheelchair accessible is a huge undertaking since all doorways need changing the kitchen needs redoing. Like mentioned if you have the money anything is possible it is not just changing the shower

Slab or crawlspace?

Contact a reputable general contractor who has done this job previously. He'll have an architect if he needs one.

I highly recommend hiring a contractor that has a CAPS certificationhttps://www.aarp.org/livable-communities/info-2014/using-an-OT-or-CAPS.html. They can come out and assess your home and recommend ADA modifications to fit your needs. They also have resources and training to not only make it accessible and safe but also make it look nice and not institutional. It can be very overwhelming and costly to do some of these projects but with a knowledgeable professional that specializes in this kind of work it makes it so much easier and in the long run more cost efficient and headache free.

We recently remodeled a 1980’s bathroom to make it accessible for me. Our contractor had a CAPS certification and was so helpful in walking us through the process and in the end gave us a bathroom that was both beautiful and safe for me.https://www.houzz.com/discussions/5639661/accessible-bathroom-remodel-for-a-1980s-bathroom

Beatrice, as a CAPS designer, I strongly recommend that you check out Mary Beth's link above to find one local to you. Changing people's kitchens and baths is what I do, and I'm also focused on adapting them to make them functional, as well as attractive. That's exactly what you need, in your location. You haven't responded to any of the posts, but I do hope you are reading them! Good luck!

This may not be relevant to your question, however, when my dad had a stroke that left him paralyzed one side, my mom removed the tub in her second (not master) bathroom and had a walk-in shower installed in its place. It worked perfectly for them.

The original builder did the work for her. It had no effect on resale when the time came.