I always remove the plumbing and sink first. Is the sink a drop-in or undermount? If it's a drop in, tape around the edge of the sink to protect the countertop, then start carefully cutting underneath the sink edge with a thin knife blade or utility knife. Once you cut thru as much of the silicone as possible, start working some shims under the sink edge. I find the plastic shims work much better for this job than the wooden ones. Use a spackle knife to go around the edges again and finish breaking the silicone loose.

I've dismantled a few kitchens and can say that whether you can save the countertop will depend on how it was installed. First, hope that it's not glued on! Look underneath for screws in the corners and along the top frame. Usually, after removing the screws, 2-3 people can give a quick pull on the top and it'll pop off.

Once the top is off you can access screws that are holding the cabinets. Remove the drawers and look for screws behind those also. Some cabinets have plugs covering the screws so you may not easily see the screw heads.

Re: the oven; The door should come off first. You can usually find the specs for the oven online so I suggest you do that before tackling the oven. Each brand is different so if you can't find the specs, call the manufacturer and ask how to remove the door.
Once you get the door(s) off, look for screws along the edge of the frame. Remove those and the frame should come off. You should then see more brackets/screws that are holding the oven in place.

We are installing a wall oven - I guess removing it would be the steps backwards. First you want to remove any trim peices that may have been installed after the oven was put in place. There should be one on the bottom but there may not be any more - depends on how well the oven fit in the opening to begin with.

You will also need to disconnect the wires - the cord may not be long enough to remove the wall oven all the way out before this is done.

My oven has screws (one on each side) on the inner side of the upper door opening to keep it from tipping - they have to be removed. The doors must be removed, usually they just lift off the brakets - my instructions have lots of warnings about NOT trying to lift with the doors - you can bend or break them.

Is this a double or single oven? Mine is a double and weighs about 350 lbs - not something one person can deal with.

When we dismatled our old kitchen, the laminate was not attached to the cabinets, so the whole thing lifted right off. We disconnected the drain and water and left the sink and faucet in place.

Cathy

Good point Cathy. No need to remove the sink if it's going with the countertop!

Thank you both. These are excellent hints that I would not have immediately thought of. I'm hoping they didn't use glue on the sink or countertops. And I'nm hoping no 'surprises' as I reveal the kitchen walls. I found mice nests in my last kitchen.

I had quite the surprise in a customer's kitchen. Taking the cover off of the back of their stove revealed a "massacre" of mice. The three terminals for the oven cord (hot wire 1, neutral, and hot wire 2) had a dead mouse laying from hot terminal 1 to neutral and another dead mouse sharing the neutral terminal to the 2nd hot terminal. I swear they must of planned this display (:

I install cabinets and you should look for screws joining the cabinets toghter in the face frames or just inside behind the frames through the plywood