Here's the situation: I like to place buy orders when the market is closed. However, I do not like to wake up at 630 (pacific time) to set a stop order to sell the stock. Is it possible on merrill edge, or any other brokers, to set a stop when it has not yet been filled?
Yes it is possible, as long as the broker you use allows conditional orders.
I use CMC Markets in Australia, and they allow free conditional orders either when initially placing a buy order or after already buying a stock.
See the Place New Order box below:
Once you have selected a stock to buy, the number of shares you want to buy and at what price you can place up to 3 conditional orders.
The first condition is a "Place order if..." conditional order. Here you can place a condition that your buy order will only be placed onto the market if that condition is met first.
Say the stock last traded at $9.80 and you only want to place your order the next day if the stock price moves above the current resistance at $10.00. So you would Place order if Price is at or above $10.00. So if the next day the price moves up to $10 or above your order will be placed onto the market.
The second condition is a "Stop loss" conditional order. Here you place the price you want to sell at if the price drops to or past your stop loss price. It will only be placed on to the market if your buy order gets traded.
So if you wanted to place your stop loss at $9.00, you would type in 9.00 in the box after "If at or below ?" and select if you want a limit or market order.
The third condition is a "Take profit" conditional order. This allows you to take profits if the stock reaches a certain price.
Say you wanted to take profits at 50%, that is if the price reached $15.00. So you would type in 15.00 in the box after "If at or above ?" and again select if you want a limit or market order.
These conditional orders can all be placed at the time you enter your buy order and can be edited or deleted at any time.
The broker you use may have a different process for entering conditional orders, and some brokers may have many more conditional orders than these three, so investigate what is out there and if you are confused in how to use the orders with your broker, simply ask them for a demonstration in how to use them.
why not just use a conditional order (http://www.investopedia.com/university/intro-to-order-types/conditional-orders.asp)? Like a one triggers one order? an order like this lets you place a buy order for the stock and if its executed another order is automatically placed. you could choose to let your second order be a stop order.
so here's a company that offers stuff like this as an ex. (https://www.tradeking.com/education/tools/one-triggers-other-order)