Again, not talking you out of starting to buy some gear, but I regularly image all night with my 8" with a 12" foam extension and nothing but stubbie cooler on the finder. Haven't been stopped by dew affecting guiding or dew on secondary for over 3 years, working from Bris and surrounds.
The QHY9 doesn't seem to attract dew on its casing, probably due to warmth coming from cooling unit. Body of the OTAs frequently literally running with dew (or frozen solid as happened at Leyburn the other weekend
)