Is 3000 PSI enough for latex wall paint?

Yes. 3000 PSI handles standard interior and exterior latex, though thick paints may need slight thinning and the right tip size.

What tip size should I use?

Use a smaller tip (around 0.015 to 0.017 in) for thin stains and a larger one (0.017 to 0.019 in) for thick latex. Match the tip to the paint's thickness and test on scrap first.

Does it come with a spray gun and hose?

It ships as a sprayer unit with a gun and hose for airless spraying. Check the box contents for the tip size included, since you will likely want spares.

Can it spray stains and sealers?

Yes, with a smaller tip and lower pressure. Thin materials spray well, but reduce pressure to avoid overspray and runs.

Expect real effort: flush the pump, hose and gun with water or solvent right after use. Leaving paint in the system is the most common cause of clogs.

Is it better than a handheld sprayer?

For whole rooms, fences or exteriors, yes: it moves more paint with less refilling. For trim and small touch-ups, a handheld or an HVLP unit is easier.