Please experienced people in this area--need help figuring out how much to sell my painting for!!!!?

i am an art photographer, but this is good for any 2D artists. add up what art supplies you bought for this project, the canvas cost, plus what you think you are worth per hour times how many hours you spent on it. this should get you in the ballpark. then sometimes i round up to the nearest $10. you basically want to charge him what you would like to get out of it if you were to sell it in a gallery and had to give the gallery 40% commission. hope this helps.