How many different colors are you spraying? How familar are you with the gun?
Prep time is crucial. Tape and plastic the windows, the doors, any trim that won’t be painted, and any walls or ceilings that won’t be painted. Tape off the doorways between rooms because over-spray is going to be problem. Are the floors protected and will the protection hold up to traffic and dragging the sprayer around on it? Prep time, depending on how you do it, could be 75% of your actual time spent spraying.
Plan on each color change to add an hour to the job.
The wall texture can double the painting time. Popcorn or heavily textured walls take twice as long to paint properly as opposed to smooth plaster walls.
Factor in all of that and a good spray painter can cover 100 sq. ft. in about 5 minutes. Figure one normal wall every 7-8 minutes. A ‘normal’ living room can have all four walls covered well in about 30 minutes.
Add 20 minutes if you are painting the ceiling. Paint all the ceilings first. Then mask off the ceiling for at least two feet in the first room painted and mask all the ceilings in turn. Then change to your wall color and shoot the first room.
This is all based on you knowing your spraygun and working hard and smart. When I was a professional painter my partner and I could mask/paint/clean up a typical 2 bedroom 1000 sq. ft. apartment in about 4 hours. That was for your standard flat light tan walls and semi-gloss white ceilings/bathrooms/and kitchens. We worked fast and hard but it wasn’t hard to do two apartments a day if you coordinated your efforts.
And don’t forget to wear a hood and face mask and a breather. Those paint fumes and particles will kill you in hurry if you don’t! Just a word of warning from someone who has lost about 40% of my lung capacity to latex.
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