After you have done the multiplication, subtract about 40 sq feet per window, and about 60 sq feet per door. Divide by 400 (interior paint covers 400 sq feet per gallon). The number that remains, is how many gallons you will need. If doing multiple wall colors, then you should do this process for each room (or sets of rooms) with a particular color.
Prep the house. Wash the walls, remove wallpaper, patch, spackle, seal stains, dry and sand before you attempt to paint. Now is also the time to apply painters tape for trimming, lay drop cloths, etc. Remove all outlet and light switch face plates, collecting screws in a zip-top bag (good opportunity to wash the face plates all at once as well). You can also buy your paint at this time. Don't wait until the last minute. It can take hours to mix many gallons of all your colors. Remember that traffic triples at your home-supply and hardware stores on weekends. Buy on a weekday if possible.
Use semi gloss for hallways because walls there are more likely to be touched, bumped or otherwise marked over time (semi gloss cleans more easily). However, use flat for a living room. Flat will help hide imperfections in the walls. If you want the same color in both the hall and living room, then no problem. Use flat in the living room, semi gloss in the hall, making the threshold the transition point.
Celebrating 35 years in business, Shoreline Painting & Drywall Inc is a family owned and operated company located in Norwalk, CT. We transform houses into world-class homes by using the right mix of artisans and painters, state-of-the-art tools, and five star eco-friendly materials, all under a structured management team. We engage each project with integrity, first class workmanship, and pride, and we guarantee and stand behind our work. We are fully bonded, licensed and insured.
Paint supplies cost anywhere from $10 to $100 or more depending on what you need. Painters will typically provide most of the supplies for a project, but sometimes they will allow you to pay for solely labor if you provide all the materials yourself. You might decide to do a DIY paint job down the road. In which case having these supplies on-hand will save you time and money.
Most of a projects price is the cost of labor at $25 to $75 per hour. However, most contractors bid out based on the entire project which includes all work hours. Hourly rates are only useful if your pro asks to do the job as “time and materials.” However, be wary of this pricing structure, it usually shows the contractor is uncertain how long the project will take.