How can I make over the kitchen countertop inexpensively?

You could use contact paper or paint it.

Formica painting kit.

You can use craft paint, just pour on counter, take a stong feather to pull the color around, you can do this with several colors. Once you have your colors mixed to where you want them let it sit 24 hours. Seal with clear sealer,buy at any hardware store. One that I prefer comes as cement sealer in clear. Put on at least 2 coats. Let completely dry before putting anything on it.

I'm kinda fan of the painted carrera marble look..... https://www.youtube.com/watch?v=ozLQEP_LeQQ&t=111s

https://www.youtube.com/watch?v=y0w0eoiH-9c&t=169s I suggest you find a good picture of carerra marble as your inspiration to pick up the colors and how the veins of darker color looks - they have a good contact paper that I used as my inspiration for one I painted.

When I moved into my house, they had contact paper on the countertops. I eventually peeled it off (then replaced) but it held up well. I have no idea how long it was on there before I bought the house.

Hi Nancy, here's what we did to change our counter top - cost under $100. And it is very durable.

https://countrylivinginacariboovalley.com/how-to-paint-a-countertop-to-look-like-granite/