So caked-on toothpaste probably does nothing, but uncleaned porcelain fixtures can actually be etched and damaged.

It is a 125 year old, 5000sqft exquisite home on an acre.The trim wood (not painted) is awesome and original for this home. 

Has anyone ever used a porcelain spray to refinish tiles and a bath tub?

How much does it typically cost to have a standard porcelain tub stripped and reglaze?

I believe I would be able to replace these tiles with porcelain tiling on my own; my main concern is the fact that they may be asbestos tiles.

I have come to the conclusion that a nice porcelain tile is a good tenant - proofing solution for flooring unless the property already had refinish-able hardwood flooring prior to my purchasing the property in which case I would keep the hardwoods.I am opposed to having carpeting for flooring because I feel it will be easily trashed.

It is a porcelain.

Most durable floor covering for kitchens/bath is porcelain tile.

If the factory isn't using, 5/16 or 3/4 inch plywood or at least CDX, 2x6 exterior wall construction, double pained tinted and rated windows, porcelain fixtures, granite or marble countertops, stainless steel fixtures, copper plumbing and upscale accessories they don't and will never git my biz. 

Porcelain tile will be run throughout the house.