I plan to sell my house after painting the inside and outside. Is it more reasonable to sell the house as is and provide the buyer with the money to paint the inside the colors they want?

Typically it is best to paint the house with neutral soothing tones prior to listing the house. Its better to give your house a clean look before the buyer sees it rather than offer money for repairs. This is because it changes the mindset of the buyer by lowering the perception of the quality of the purchase. You will be able to sell the house at a higher price (perhaps a few thousand more depending on market). Also the buyer can move in immediately following purchase rather than wait for the house to be repainted. If the buy wants different colors badly enough, they will repaint the house regardless without haggling down the price.