This is an awesome little sprayer - and the painted finish of my bench was even better than I expected. It's for small to medium jobs like painting furniture, cabinets, a door or trim, but a wall might take too long. It was easy to setup and use. As with any sprayer, inside you'd want to use plenty of drop cloths and masking though the spray pattern is well controlled. I used latex and thinned it with 1 oz of water per pint. With 1.6oz/pint (10%) it took a while to dry, but gave a nice finish. I wouldn't go more than 10%, but I suggest you experiment. There's a wall poster for you practice on, and a stick to help you see how much you're diluting the paint but I used a small measuring container for the water as the stick was one more thing to get covered in paint. The air adjustment works by limiting how far you can pull the trigger. The higher the number, the more quickly you have to move the spray head to avoid puddling and runs. I set it to III and moved much quicker than the Wagner videos. Air blows out when you are not pressing the trigger which I gather is good for the paint you've already deposited. The cup is 12oz so for a big job you'll fill it frequently. I used a separate container of diluted latex to avoid having to dilute each batch. When the level in the cup gets very low it can spit paint if air gets into the pickup tube, but this isn't a problem if you watch the level. Cleaning was easier than I expected. I used both methods in the instructions after each use - spraying clear water and taking the nozzle apart and washing the parts in soapy water. That seemed to be needed to get everything clean. For oil based products you'd use mineral spirits. All in all very good product.