@Cassandra Weesies yep, some good comments here. I’ve used them all, and I’d say the more expensive paints are pretty thick and suck for wall coverage/ time efficiency. I like the thicker high quality paints for painting eaves and facia with a 6” roller 1/2” nap. Otherwise on interior walls a couple important pointers to mention that haven’t been said yet is, the sheen is really important too. And here’s one of the bigger things to take to heart; if you use flat paint on ceilings it will hide a lot and I’m now a fan of using flat on the walls when I can, if there’s imperfections. On rentals this is a bad idea for walls, but a flip it can save you time and $ and cause a better look. I go for the 2nd or third cheapest paint which is usually a good quality without paying for the scams.
For color, varying whites are cool. Swiss coffee on walls is cool with a brighter white on trim, but I’m still figuring out my whites. For doors and trim, go for a semigloss or satin.
Blah blah blah, it all works, but there’s hundreds of paint tricks you have to learn over the years