Carburetor (BBD) - new or rebuild?

I usually start out by trying carefully to disassemble the carb without damaging anything, AKA the top/ bowl gasket. Clean it up, lube the accel pump, use pressure carb cleaner through the passages, then air, and then try it and "see where you are." You might get lucky and need nothing else, or you might have a bowl gasket leak but it runs good, and you know then, that if you buy a kit, you have a great "shot" at success.

I admit, that in this day and age, and as old as these carbs are getting to be, 'specially some with oddball schemes for power valves, etc, it is more difficult to "pull this off"