Depending, are you going to be “investing or trading”. For investing you could have one BS Asset - Shares account or you could have individual BS Asset - Share accounts - depending on the number of stocks you are planning to hold. If it was greater then 5, you could consider using the Fixed Assets tab. When the Custom Control Accounts feature arrives you will be able to create a Shares group within that tab. For investing, keep the total cost together, don’t separate out the brokerage.
For trading, you could use the Inventory Items tab - a stock of various share holding. Here you have the choice of separating the brokerage and allocating to a P&L expense account