The caulking is drying more and more gold and I am sure he did not use the same Almond he used when he was here last and just wanted me to return the battery charger he left here so he did as little as he could to cover the cement area between the carpet and tiles in the front foyer despite giving him a metal transition piece I bought that he did not want to use. I wanted the caulking to match the mushroom grout. The goldish colored caulking is still soft and not dry so I wonder how long it will dry with my floors so cold despite keeping the room at 71 degrees? I have to block that area so will take pictures when it is dry. The middle foyer's metal piece was glued on and a piece of wood was not placed on the 2" cement area in between the tile and carpet so he could nail down the transitional metal piece I bought for him. I hope it does not look too bad when it dries. I hope I can live with this until I have time and money after my busy season to replace this carpet. To me not finishing a job is liking making a beautiful dress and not cleaning lint and dirt off of it and not hemming it so the edges are frayed.

Peroxide is the same product that is in the tooth whitening products. It's also very inexpensive and less caustic than other products. Bleach is quite effective but I suggest starting with the peroxide since it most times does a good job. Before using any of the more expensive specialized products, peroxide or bleach have been very effective on coffee stains that discolors white grout on tiled kitchen counters as well as white shower tile grout and most homes already have them there. You may as well work your way to the product that does the job to your satisfaction since the issue will eventually resurface sometime down the road. I think you'll find the least expensive approach the way to go. Test a small area and see what results you get. pour some on, press a paper towel onto it, add a bit more and let it sit for as long as the towel remains wet. If you're in a big hurry to get it done fast, you'll have to use the more aggressive approaches but, if you can wait a few hours, they are not needed. Treat the spot, go to work and when you get home, you may be delighted with the results.

Maybe it depends on where you live and how humid it is inside and how good the ventilation is in your bathroom. I am in the Pacific NW which is not exactly the desert, and I have never in 30 years had mildew on any surface in the bathroom. I'm not Susie Homemaker either, and I wait to see stuff rather than do "pre-emptive" cleaning, if you know what I mean. I have seen the pink stuff (bacteria, not mold) that grows on grout and behind caulk before, though! On the epoxy grout, it shows up only down near the bottom row of tiles and it comes right off without serious scrubbing. We always use liquid soap and spritz with an after shower spray once in a while. I agree a yellowing of white grout with those tiles would not be good, but I bet you could get away with a gray.

The best way to reduce grout maintenance in a shower is to use the right grout in the installation. The old cement-based grouts were hard to keep clean. Many seemed to grow mildew like it was a cash crop. The newer urethane grouts are essentially a durable plastic, non-porous, and do not provide hiding places for mildew. We use nothing but in our bathrooms on floors, walls and shower surrounds. It's more expensive than cement grout, but considering the overall cost of a tile job, the different is minimal. Quartzlock was the original urethane product. It has now been bought out by Bostik. It is definitely a pro product, not recommended for any but the most experienced DIYers.