Screw in dipstick is normally a Kawasaki engine. Remove dipstick, wipe, turn to the left until it seats on top of threads, and pull it out for reading.
I have only seen a larger twin Honda on one zero turn, and it was a Hustler. Unless the engine is leaking a lot of oil, I would just keep the oil checked and topped off and run it. Customers come in periodically throughout the year with oil leaks. I pressure wash the equipment and can rarely...
Hustler is a decent mower. Just keep the one you got for 2 acres, 12” is not that big of a difference. The hours, engine type, hydros, brand, condition and features determine the value of a zero turn.