Sure looks in the picture like moisture is getting under the vinyl. The most likely cause is the wax seal under the toilet. The two white covers shown in the picture cover the screws that hold the toilet down. You can pry them off with a screwdriver. Try tightening the nuts just a little and see if they are loose. If they are, tighten them, but not too much or you will crack the base of the toilet. If they were loose and you tightened them, wait a week or so and see if the stain gets any worse. If it does, it is probably the wax seal that is bad. As far as getting a plumber....do you have the knowledge to change the wax seal? You can get a "how to" book at HD. The wax seal is only about 59 cents. If you are at all handy and have some tools, you can probably do it.

redroze, you have such exquisite taste in making every room you decorate feel so peaceful as well as beautiful. I just love your finished guest bathroom so much. It gives me a lot of ideas for when I am ready to renovate my bathrooms. I love the white vanity with the crystal knobs that goes so well with the peaceful wall coloring, tile and hardware. Your bathroom is truly breathtaking to me. My three bathrooms in my home are more difficult to decorate since the toilet, sinks, bath tub, jacuzzi, etc. are all bone and not white. One day, I want to change all this in my Master Bathroom. My Master Bedroom is so peaceful like your bathroom with my Antique White Maple Durham Furniture and neutral walls with ivories, creams and whites. My Master Bathroom I managed to make peaceful and work with the bone appliances. I guess I am blessed that they are not pink. :) Thanks for sharing.

It should be a no shoe environment, as heels or bits of gravel caught in the soles can chip the glass and make sharp edges. There are specialty glass tiles that have a textured surface that are designed for a bath area, because glass is slippery. If you use the small 3/4" size, that may not be necessary, but you also need to make sure that you use a sanded grout for traction. That can scratch the surface of the glass slightly, and that can hold a bit more dirt than installations with unsanded grout. If you have family members who will be using the bath who are mobility challenged, you may want to be sure that you only use it in some type of decorative "stripes" and combine it with a regular tile with good traction, plus prep the walls to install grab bars now or later.

If it ain't broke and you don't need the latest style I'd just put it back. The valves and flappers fail in all toilets over time, there's no reason to replace the whole thing to repair those problems. If you needed to go to a lower flow, or had one of the '90's toilets that never actually worked that would be a different story. All that said, I'm very impressed with the new Toto's we put in our house. Not very expensive, work perfectly, refill quickly and quietly.