Tear Out and Disposal of the Old Tops
The old surface has to come off before the new one goes on, and that half hour causes more disputes than the rest of the job combined. The scheduling notes at countertop installers redding aedreams cover tear out separately, because a Redding countertop quote that omits it is not cheaper, it is incomplete.
Somebody Has to Disconnect the Plumbing
Water off, supply lines disconnected, trap broken, disposal unbolted, and the same in reverse two days later. Some installers do it and price it. Some will not touch plumbing for liability reasons and expect you to have arranged it. Ask which, and ask about the gas line if a cooktop is involved, because that answer is almost always a licensed trade rather than the install crew.
Nothing Comes Off Cleanly
Old material is glued and screwed to the cabinets, so demolition means prying, cutting and occasionally breaking it in place. Expect damage to the cabinet tops, to any tiled backsplash, and to the wall paint behind. That is normal and not carelessness, but it does mean the backsplash decision is really being made now rather than later.
Where the Old Surface Goes
Stone is heavy and most transfer stations charge by weight, so disposal is a genuine cost rather than a padded line. Laminate is light and cheap to dump. If the existing tops are in good condition somebody may want them, and a few hours on a local listing occasionally saves the fee entirely, though it will not save you the labour of carrying them out.
The Gap Between Tear Out and Install
Where templating happens after removal you are without a kitchen sink for the full lead time, which can be a fortnight. Some shops template over the existing surface and adjust, shortening the gap to a single day. Neither approach is wrong, but they are very different to live with, so establish which one you are buying.
Put It in Writing
Tear out, haul away, plumbing disconnect and reconnect, and who patches the wall. Four items, one sentence each on the contract. Bids that look hundreds apart frequently turn out to be identical once these are lined up, and that is worth finding out before rather than after.