Costs will vary quite a bit, based on where you live, what you're hoping to achieve, etc., so you may want to contact a few contractors/designers in your area to get a more accurate estimate.

Houzz published an article about this though. It may give you some ideas to start with. Good luck on your project!

https://www.houzz.com/magazine/bathroom-workbook-how-much-does-a-bathroom-remodel-cost-stsetivw-vs~23875885

True it all depends on what you are trying to achieve. Are you going to entirely remove the shower and install a new one and what kind? All tile? Will you have to move plumbing?

Instead of looking at the costs of a new bathroom, I would look at your finances, see what your budget allows you and set that as your price to work within. If this were my bathroom, I would keep the shower. I like it. I would have a sleek, hinged glass door installed. I would get a new vanity or keep the one you have and get new counte rtop and skin. I just got a new Toto toilet that cost $450, to give you an idea. You can also get toilets that are much less expensive.

I would say that doing what you like within budget is first, but I wouldn't put more money into your home than the market can support if you were to resell. I agree that the shower looks nice, unless it's damaged in some way, I would keep it and add the glass door as suggested. The toilet looks to small. I replaced mine recently for about $275. I would paint the walls and the vanity to match the tile, it will make it seem larger. Remove the plate mirror and get one with a decorative frame. Replace the fittings. Replace the counter with a carrara look surface. I would take off the soap holder and replace it if you can match the tile, otherwise leave it. If you replace the sink with a vessel style the soap holder tile replacement may not be as noticeable. The place you can have a lot of impact is the window treatment. I think the white one pictured below would look best if you go with the all white, but if you want a punch of color, I love the large scale bold prints. My guess is, if you do it this way, it would cost about $2500, unless you do a slab vanity. Given the size of your vanity, you may be able to find a remnant though which would save you quite a bit.

oops didn't include a pic of the shower , Not installed yet window treatments and towel bars, thought included in my cost.

Kathy, I love your wainscotting!