Marble can be restored by a stone restoration company. We have one near us that does fabulous work. Read up on the process here:

http://www.nsmarble.com/our-products-and-procedures/

Great to know, Dragonfly. I am so glad yo asked this question HM. I am installing marble bathrooms as well and have had a few second thoughts (but not enough to dissuade me :-)

Marble has been used for centuries. Back in the day, it was considered low maintenance. We work in many historic homes and you would be surprised by the condition of the old natural stone surfaces. Restored occasionally (over many decades), and not at a great expense, it is timeless. But our society has changed and with the evolution of new technologies and related products, preferences for the "easy to care for" product have grown in popularity. Yet natural stone will always have its place. If you don't have a water softener, or you have high iron content, these things can contribute to damage to the finish of marble (and other natural stone). These considerations should be taken into account. Of course, today you also need to have a "buyer beware" approach to marble as some of the inexpensive marble is a lower grade, softer product (prone to more issues than the higher quality). While we install plenty of man made tile, the majority of our bathrooms are still natural stone. We do have a higher end client base and for whatever reason that tends to be their preference. We are also in the Midwest and trends are slower to take hold. There are regional differences. While there are a few marble "look a-likes" that are pretty good, most appear fake to those of us who have been real up close and personal with marble on a daily basis for decades. But that's not important to everyone. Obviously it is an individual choice based on the homeowner's lifestyle and tolerance. You need to love your choice for multiple reasons.

Marble is timeless and relativity easy to maintain if you do it proper. Stick with a polished surface and not honed. Do not allow powdered makeups or liquid soaps to sit on the surfaces of the marbles for long periods of time. ((These are the most common stains my customers ask me how to remove)) Use a solvent based sealer to seal with as they repel oils much better than a water based sealer and will last longer with proper maintenance. And as Dragonfly mentioned, quality of your water can have a big impact on marble. Please take that in account when selecting your product.

Thanks everyone for their reply. I feel good about my choice to go with marble knowing that it can be restored should it get stained or etched. The tile place I’m buying the marble from suggest Stonetech Bulletproof sealant - is this a good brand? And how often? The bottle says the seal can last 3-5 years - sounds too long for me. Most everywhere I read say to seal annually. And are more coats better than one coat? Or it doesn’t matter and additional coats are just a waste of sealant?

If you have a qualified professional installer, I would ask them what sealer they use (and why). There are a number of quality products, and all the seasoned pros will have their preference. How often to reseal really depends on the use that the surfaces get. Most of our clients do it every three years or so. We use the Miracle Sealants products most of the time: time:https://miraclesealants.com/products/seal-protect/511-porous-plus

Good luck with your project.

One more thing: do NOT let a "cleaning lady" use her normal cleaners in there! The most amount of damage is done by "hired help". They drag in their mops and their cleaning products (often in unmarked spray bottles) and go to town.

If you do NOT tell the cleaning lady about the marble, you will have a ruined marble floor. I guarantee it!

If you are going to have marble (and I'm pretending that you have a cleaning lady) I HIGHLY RECOMMEND you purchase and PROVIDE the cleaning/maintenance products allowed in your home. Tell the cleaning lady (or man...I'm not picky) to leave her/his stuff in the car and use YOUR products and YOUR mops and YOUR tools in YOUR home.

And then educate them about marble. This will go a LONG WAY in keeping your marble happy. And when you sell the house, I would leave the marble cleaning products in the house with a cheat sheet for the details of what is done when and by whom. Put a bow on it. Call it a house warming present. Whatever...just be fair and let the next person know what works.

SJ, Very good advice. When we install marble (or any natural stone) the client get a "cleaning lesson" from us AND a final gift package of appropriate cleaning products.

Thank you so much for all the great information and insights. Thank you OP for starting this thread.