Dynamic card game

A new card game is available at a casino. It uses a well-shuffled deck of $8$ cards, half of which are red and half are black. The dealer will draw cards one by one, without returning them to the deck. You have the power to stop the game at any point (including before any card is drawn). Each time a red card is drawn, you win $1$ dollar, but if a black card is drawn, you lose $1$ dollar. Think about the best strategy for stopping the game to maximise your expected payoff.
What is your expected payoff under this optimal strategy, i.e. how much (in dollars) would you be willing to pay to play this game?