The companies with the best paint products are Benjamin Moore, Dunn Edwards, Sherwin Williams, and Vista Paint. As a painter I don't recommend Berh from Home Depot as much because it's quality is just marketing. Flat paint has no sheen and it shows its true color, but is not easy to wash or clean. Satin, eggshell have low sheen and is washable. Semigloss ang glossy has a high sheen and these paints are recommended for bathrooms and kitchen or where there's high humidity and steam.
Freshly painted walls often look blotchy. The color is uniform, but the sheen isn’t consistent. This usually occurs over the holes and cracks you patched with a filler or drywall compound. The porous fillers absorb the paint, dulling the surface (a problem called “flashing”). When light hits these dull spots, they stick out like a sore thumb. The smooth patch also stands out in contrast to the slightly bumpy texture of the rest of the wall. A quick coat of primer is all it takes to eliminate ﬂashing and texture differences.
The materials of the home’s facade should be considered before painting your home. When painting flat surfaces like siding or wood, you can opt for standard outdoor paint. When painting a textured surface like stucco or brick, “elastomeric” paint is a much better choice. This type of paint can stretch more than normal paint, which allows it to bridge over small gaps and crevices, painting smoothly over texture.
O'Neil patches shallow holes and divots with Ready Patch because it dries fast, sands smooth, and stays flexible. Deep cracks and rotten spots are best repaired with two-step epoxies, such as those made by Advanced Repair Technology. (For a step-by-step instructions, see Repairing Rot with Epoxy.) The days of using polyester auto-body fillers on wood are over. "They cure too hard," says Portland, Oregon–based painting contractor Kathleen George. "They look good at first, but then they peel away."
Also prime the ends of adjoining boards. This step pays off by slowing the moisture penetration that can lead to peeling at the joints. If the new siding is redwood or cedar, buy a special “stainblocking” primer. Both of these woods contain natural chemicals (tannins) that can bleed through paint, causing brownish stains. A stain-blocking primer will seal in the tannins.
Back to the article. You can add water to all latex based paints / thinner to oil based paint. The tinting base has absolutely nothing to do with it. Say you are working outside and throughout the day you have to add a little water to keep the same consistency. If somebody really tried to add 20% to 50% water they no longer would be painting they'd be performing a whitewash or pickle finish.