Beth sells candles from her website. She can get a candle from her suppliers at a cost of $3 to her. The candles have been selling for $5, and at this price, consumers have been buying a steady 4000 per month. Beth would like to raise prices, but a market surveyor told her that for each increase of $1 in the price of an candle, she would lose 300 more sales each month. At what price should she sell the candles to maximize her profit?