Clean it, paint it, get some white towels and a mat for the shower and in front of the sink, fresh flowers, a candle, some art on the walls. Everything looks the same color now, so I'd work to find a pretty paint color for the walls. Frameless showers can be pricy, and can take a couple of weeks to fabricate.

I'd upgrade faucets to something trendy. Paint the gold trim on shower to a chrome. I'm not a fan of towel holders but I like the mirrors.

I agree with comments above. Upgrade the plumbing, love the idea of painting the shower trim to chrome, and maybe consider painting the cabinetry. Pretty simple, quick fixes.

I uploaded the wrong photos but you two got the general gist. Thanks for the idea about painting the gold trim on the shower! Excellent! Love the faucets too. Here is a better photo :) It's been cleaned and painted and I now have some art on the wall. As we can spend about $10k in upgrades. Thanks again both of you!

You may also consider updating the light fixtures as well to finish off the look.

To me, thinking like a potential buyer, the biggest turn-off or concern would be the outdated glass block window!! I'd worry less about inexpensive cosmetic fixes that a buyer with a good eye could do themselves and think about replacing the window! Windows tend to be expensive and need professional installation. If you can get one done in expensively, potential buyers may be more willing to consider taking on the cosmetic stuff in there.

New lighting fixtures - DEFINITELY! Regarding the glass block - the community where this home is located, just about every one has these glass block windows in the baths and people LOVE THEM. I appreciate what you are saying about not worrying about the small stuff people can look beyond... I am hoping one of them shows up soon!

wonder what the age demographic is in that community? To me, glass block screams 1980s and outdated, but to each their own! ;)

If you have 10k to spend I think you can do it.

Below estimates include approx labor & mat:
A frameless glass shower door like that set is about 3k.
A new vanity with sinks granite tops faucets etc can be like 2.5k
Rid of glass block. New window with trim approx 2-3k (high side)
Paint $750
Electrical and lights $500
Misc: $750

Tile floor looks workable to leave in photos. Can't really tell. Just clean grout if needed.
I would skip the tile on the walls in your situation. Can't tell from photo but if it matches the tub and tub splash I would leave it in your situation. Focus on the other stuff.
I think you can make it look much much better.

Someone mentioned that new counters and sinks would be about $2500. Where I live, I was able to get new granite that came with free sinks (there were 2 or 3 nice choices), for under $1000. It is 9.5 feet long! I also had a handyman raise the whole vanity to the new 34" height with basically some 2 x 4's. it was not expensive at all. The height and the granite were the focus of the room. I would tape off the brass shower trim and paint it black, and paint the vanity light bases black too. You can also switch the pulls on the vanity to black, and it will look sleek and upscale for a minor expense. Shop around, check out various places, and choose an inexpensive but nice granite (I chose a medium grey with no real veining, and tiny variations, so it looks nice even when not squeaky clean). I think it was under $2000 for all of that. The wall paint was a separate cost. New faucets removed the tub's fake crystal balls and replaced them with the "cross" style. Easy to use and timeless; they were also lifesavers as the tub was installed with incorrect faucet bases 25+ years ago, and a lever style left one of them pointing the wrong way! Found a nice sink faucet to complement that, at a less expensive hardware store. One of my favorite updates to the house! BTW, a grey paint, suggest March Wind, would look amazing with the yellow tones in the room.