So if all that you are doing is replacing the tile countertop and sink and backsplash then all you need to do is go to the local stone slab place and pick out the appropriate sized stone to replace the tile with. The recommendation i would make is to pick a synthetic stone because the repeating "texture and patterns" are compatible for the butt joints assuming that you will have that issue, and the water staining / heat sensitivity factors are favorable like they are for granite.
the first thing is the tile and sink will have to be removed... normally that is going to have been installed on top of a plywood slab which is screwed to the top of the cabinets so removing that from the cabinets will require some skill and patience to not make a mess out of the cabinets.
Are you sure that you do not want to replace the cabinets? My experience with kitchen remodels is that it is often like a pregnant cat ~ its the gift that keeps on giving. In other words, as you upgrade one surface, the other surfaces then look dated and the wife is back to being unsatisfied and we all know how you will feel about that.
So after you remove the old tile / plywood top a new plywood top needs to be crafted as the base for the new stone slab. No big deal, a modestly skilled remodelling carpenter can do all of the above. The cutout for the sink is created from the sink template and if you are switching to a larger sized sink then your base cabinets under the slab may no longer be the correct correct size. If you do have room for the larger sink without underlying cabinet adjustment then great.
Once the base and sink cutout are correctly positioned you then have the slab installer cut and attach the slab stone to the correct dimensions which they will have measured for. Make sure they do the measurement so that it is their problem if the dimensions turn out to be incorrect. The sink and new faucet arrangement will get installed by the plumber before or after the slab is installed [usually before if the lip is below the slab].
Today's cool as a cats ass backsplash concept is the glass tile sheets... can get them in all colors and are easy to install [for the tile guy that is] and do a good job of unifying a kitchen remodel. Good luck. A piece of advice... source and get all of the materials on hand before the installation and line up the sequencing of subcontractors that you will need to operate in the correctly timed sequence or you will be doing the dishes in the bathtub for an extended period of time which is a real buzz killer.
Here is an example of what we did for possible ideas ~ this turned out great. P.S. If you get out of this without replacing your appliances you are a master of the universe and I'm going to want to interview you for your mind control techniques for controlling your wife's thoughts and desires for obvious reasons.
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