I know that I should take into consideration commission and liquidity costs (bid-ask spreads) when considering placing a trade, however I am not sure how much should I worry about those? For commission I can pick broker with lower fees and try to negotiate better price, and for liquidity I can limit myself to trade only highly liquid options. Is there anything else here that I should worry about or do?
How do you estimate these costs and account for them when trading?
How do you estimate these costs and account for them when trading?