PERSONAL ACCOUNT

A personal account has a portfolio and funds available.
The investor's portfolio tracks how many shares they own of each stock.
Buy trades made from a personal account are free.
Sell trades made in a personal account are immediately charged a 5% fee.

                              TFSA ACCOUNT

A TFSA has a portfolio and funds available.
The investor's portfolio tracks how many shares they own of each stock.
Every trade (buy/sell) made from a TFSA is charged a 1% fee.

                              TRADE

A trade can be: MARKET_BUY or MARKET_SELL.
A trade is identified by the:
  - stock (AAPL, FB, GOOG, TSLA).
  - type of trade ( MARKET_BUY, MARKET_SELL ).
  - the amount of shares being purchased/sold.
  - the price of the stock at that day.