Generally speaking this would increase the value of your home $5-10K (Can't give you a % without the value of your home.).
Aside from making your home more liveable it would make your home stand-out from the competition when you go to sell/rent down the road. People are less and less willing to share a bath than they once were so they value having separate facilities whether they are renting or looking to buy.
If investing in a new bath upgrade steer clear of very personal color or style choices if you are planning on selling in the near future. Buyers are always excited about new kitchens and baths but trends change quickly and you want to appeal to broadest taste possible.
In planning your renovation, don't forget to check with the condominium association about their requirements so you don't experience unnnecessary frustration or expense.