How Wash Sale Rule apply to a day trader in Stocks, making 50-60 transactions per day, how losses are adjusted if i keep buying a falling stock to break even and sell?

Situation: I buy a 100 shares at $10 (lot A), then another 100 at $9 (Lot B), sell 100 at $9.5 (Lot A = 50$ loss), Buy 200 at 8.5 (lot C), sell 200 at $9 (lot B = no loss, 100 of Lot C = 50 gain), sell 100 (lot c) at $9.5 = $100 gain? Under FIFO Rules.

Same Situation: The 50$ loss of Lot A sale is added as cost in the final price of lot B or lot C thus reduce gains from 150 to 100$. Is this correct understanding?

Which rule will be best to manage this FIFO or LIFO?