Better to replace doors or paint them?

We bought this builder grade new home a few months ago but never really liked the color of the cabinets, but I'm debating wether it's better to replace the doors or paint them. It seems they are stained a dark brown almost black color. I tried sanding one down and did manage to reveal the original color but it seems like it will be tons of work to sand down all of them. What would it normally cost to paint something like this a much lighter color (beige). I'm in Texas, US if that helps.