Assuming you're dealing with ordinary investment instruments like stocks and ETFs, this basis information is typically tracked by the bank or brokerage where you buy and sell them. (money.stackexchange.com)
As for point 6, there are far more limitations in accessing capital from alternative investments than from ordinary investments. (alephblog.com)
Writing and purchasing call and put options are specialized activities and entail greater than ordinary investment risk. (advisorshares.com)