Investment specific transactions are just like general transactions except they have four additional fields: security, units, unit price and commission. You can only set investment specific values when recording or editing a transaction if its transaction type is an investment specific transaction type. The investment transactions recorded in an investment account will be used to generate the holdings for the investment account and for the overall Portfolio. Recording investment transactions can be done through manual entry, account downloads and importing files.
When recording investment transactions the Buy transactions will decrease an account's cash balance and while the value of the account's holdings will change by the market value of the shares of the acquired security. Sell transactions will increase an account's cash balance while the value of the account's holdings will change by the market value of shares of the relinquished securities. The change in cash balance and market value of held securities will offset each other in the account's total value (cash balance plus the market value of holdings). Whether or not they completely offset one another depends on the current market price of the security and if any commission was involved.
Recording investment transactions can also involve cash transfers. For example, a Buy transaction may be funded by cash in another account at the same institution. To indicate the cash involved in an investment specific transaction came from or went to another account you can set the transaction's category to be the other account's category, that other account's name in brackets, to indicate a transfer. If you do not want to track the cash involved in an investment specific transaction you can set the transaction's category to be the account the transaction is in, the account's name in brackets. Doing so tells the program not to apply the cash involved against the account's cash balance. For example, employer matched retirement accounts might not have the cash transactions listed in their downloads and categorizing those transactions with the account they are in will keep the account's cash balance from being affected and left at zero. Some institution's downloads even indicate the cash source/destination is undefined and there's an option in the Investments-Importing preferences to prevent transactions with an undefined cash source/destination from affecting an account's cash balance which will automatically categorize those transactions with the account they are in.