What are your goals for the closet? That might shake some posters out of the trees. Personally, I'd do double doors, maybe even split half way up, so you have upper and lower double doors. OK, while I'm dreaming, bottom half would be a laundry bin. Top half storage. The way the tile is cut is problematic. AO may be able to get you a similar color in octagon and dot. Otherwise, what about buying white octagon and dot, then painting with color-matched epoxy paint before you grout? Alternatively, a clever threshold (clever because It would have to project out a bit into the room bc of that unfortunate tile cut) could bridge the space into the closet. You could get the threshold made out of anything that looks simpatico to your overall bath; marble is common, or black granite, travertine, painted or stained wood (easier to shape and cut into place!). If you did that, no need to match tile for the closet floor. In that case I'd get floor paint and paint the closet floor a color that gets along with your tile. I have a closet in my bath and the depth makes it difficult to get full use of the space in it. We use a lot of bins and trays, so we can pull them out and get what we want, or access less frequently used items stored behind them. That tile, by the way, is a beautiful, distinctive color. It may be harder to work with than many of the white tile bathrooms you see here, but I hope you keep it. It looks great! (And best of all, it doesn't look like a million other bathrooms.)

We have a pocket door on the 3/4 bath inside the master, and honestly we almost never close it. We close the bedroom swing door if we need privacy. The pocket door is there if we need it. But for a full bath going out into a hallway a swing door would be much better.

I agree with Cpartist"s layout and like moving the closet over as suggested by D M so that bedroom 3 has easier access to the bathroom. Do you have room to have the toilet face the tub and add a linen cabinet next to the toilet? How wide is the tub toilet area?

Thank you everyone for the suggestions. Really appreciated. @Carrie B I don't want families, couples, or kids. I am targeting people in their late twenties/thirties with whom I have things in common. I am very selective. 99% are people visiting the universities for a few months or travel nurses. Currently, I have a Pediatrician (last year of residency), a lab technician, and a travel nurse. And I am % sure in Gainesville you do not need a permit if you live in the house and you are homestead, I asked the city. @palimpsest it is my house, I am renting rooms just for a few extra years. The closet can be smaller, I can extend the bathroom toward the closet. Having a 5'x8' or 5'x7' bathroom on that corner is not an option, it would ruin that beautiful room @Greg GN Builders., That is a good point, but I can enlarge toward the bottom of the drawing and move the sink to create space for the person to walk. @latifolia Below is the entire floorplan Going back to the original question. I want to figure out if I can get this 4th bathroom in a way that it will increase house price values and do not look weird. What is the minimum depth of the bathroom that you think would be enough? See below the full floor plan. As you see, on the top right, there is already a 34x34 shower in the previous master bathroom (the part on the bottom of the drawing is a 2008 addition the previous owner made, the part where I live). The upper two-third of the drawing is the old house (1959). No one complained about the 34x34 shower or small bathroom and everyone was happy to pay $1400 a month for that room. Questions again are: 1) can I make the wall (which separates room from bathroom) 2.5" thick by rotating 2x4 studs (so 1.5" stud + 2x0.5" drywalls) or just using 2x2s? That would bring the bathroom shower to 34x34. 2) Can I do a pocket door on a 2'5" wall? 3) With the same studs, I could bring the wall between the proposed bathroom and the room on its left down to 2'5". Which would bring the new bathroom up to 36" of depth. 4) If I need an even deeper bathroom, I could move the wall by 5" into the next room. As you see the window is off-centered by exactly 5" in that room, moving the wall by 5" would bring the depth of the bathroom to 39" or 41" depending on executing only (1) or also (2). Honestly, I would prefer not to move that wall, it is an extra cost. What do you guys think?