With kitchen counters that thick, I believe they face the counter with a layer of ply to support the stone. I wouldn't think that the sink would have problems with the thickness, the weight of the stone and the sink might make the slab crack if not supported across the vanity span. You could post this question over on the kitchen forum too.

Thank you all very much! We thought we would go this route instead of the standard 3-hole faucets but you know how you start doubting yourself and thinking "uh oh, maybe this is a bad idea"??? ;) They just seem like they would be so much easier to keep clean too. I like the Fairfax alot but DH wants something more modern so the hunt continues. If anyone has the Delta Dryden or Arzo, I would love to see pics of them. It's so hard to tell from the websites.

This is the first time I've posted on Houzz and I am suitably impressed with the thoughtfulness of the responses. The walk-in shower is really a top priority as my most frequent guests are my parents who are both 80...in good shape but I prefer them not to have to step over into the tub/shower combination. I am favoring the tub also for resale, but realistically resale is so far down the road that it will probably be ready for an upgrade by then and there is a tub in the master....so I guess now i'm down to tub and shower with single sink vanity and linen closet or shower and no tub with enormous linen storage and large vanity...……..I think i'll draw it up both ways and see how it looks and feels....thanks so much for all the feedback and the humor....Toby thank goodness I didn't just take a sip of my coffee or it would have been all over my screen!!

Most single hole faucets come with a plate to cover holes in predrilled counters. https://www.wayfair.com/home-improvement/pdp/fresca-tartaro-single-hole-bathroom-faucet-fbh1798.html?piid=&experiencetype=2&selectedvertical=3 https://www.kbauthority.com/fresca-fft1041bn-sillaro-single-hole-mount-bathroom-vanity-faucet-brushed-nickel.html https://www.amazon.com/Single-Handle-Bathroom-Assembly-Stainless-553LF-SS/dp/B0040YPU84 https://www.wayfair.com/home-improvement/pdp/fresca-single-hole-bathroom-faucet-w004966937.html?piid=&experiencetype=2&selectedvertical=3 https://www.homedepot.com/p/VIGO-Satro-Single-Hole-Single-Handle-Bathroom-Faucet-in-Brushed-Nickel-VG01015BN/204712741?MERCH=REC--pip_alternatives--304505547--204712741--N&