Well, you can use a pending order and set the buy/sell open price at whatever you want. But the way you have asked your question is exactly how a 'buy now' and a 'sell now' order works. When you issue a 'buy now' you buy at the ask price and vice versa for the 'sell now'.

If you end up with a position entry price that differs from where you expected it(ask/bid prices) then you may need to look at your execution times (slippage).




