With that said, here's the reality of that particular scenario. Painters do put water in the paint, but not for reasons you would think. Some materials need to have their viscosity manipulated in order to slow drying time, allowing gravity to 'smooth' out the product for a better finish. It also prevents 'drags' and 'sausages'. I personally try not to do it too often, but from time to time I have to. I want my client to have a proper finish.
basic formula? single color exterior labor only ranges from $0.85 to $0.95 per sq foot as a BASE starting point. Prices go up depending on multiple colors, slope of surrounding areas, multiple stories..etc.Some painters charge per window to mask off. Ive seen $25 a window to $50. Interiors without flooring can be factored the same way. When you start having to do multiple colors, cut ins, masking, room isolation...etc. the price jumps considerably. I always start with a base of $0.85 a sq foot and figure it out from there. the season plays a major role too. paint and materials are charged separatly and are typically marked up at a minimum of 15%. I always tell clients this. that way they pick the paint out they want and what quality they want as well. Anyways...thats your base. 1250 sq foot home @ .0.95 a ft = $1,187.50 (one color). Pressure washing, Add another $45-$55 per hour. a 1250 sq ft home is not going to take longer than 2-3 hours if its a single story.
Remember: You want to get the highest quality paint your budget will allow to ensure its lasting beauty. You'll also need painting supplies like primer, brushes, rollers and painter's tape. A professional will have these items on-hand. According to statistics, paint and other supplies account for about 15 percent of a professional painter's total cost; labor will factor into 85 percent of their charges.