We were blessed at SCR&H in Jacksonville to have a group of five or six racers who showed up the first Monday of every month to help clean the Hillclimb. We might have provided some cold beverages to help the time pass by as we cleaned and bench-raced.
I think your local weather conditions – temperature, humidity, dry-spell, rainy season, etc. – have a big impact on how often you need to clean a track. As long as we stayed on schedule, it was pretty much wipe-on and wipe-off to clean the track. The rare occasions that the cleaning was delayed a week or two made for a much harder clean-up. Especially if humidity was down or the shop got too hot and the rubber glazed over and dried to the track. That made for the worst of both worlds – a dirty looking track that was slickery as all get out.
For the track glue, we found that 1.5 bottles of Koford Medium mixed with 24 oz. of naphtha did a real nice job. Always sprayed with the HVAC system off so it wouldn't get sucked up into the AC return. We also found that we got better results by mixing the "sauce" a month in advance and letting it "ferment."
I agree with Dominator that the HVAC system plays into the equation. We always changed the filters in our two AC units before we cleaned the track since one of the returns was right over the doughnut. That way we cleaned up any falling dust from the filter change as we cleaned the track. We also found that the track stayed racier longer once we installed a programmable thermostat so the shop would stay a little cooler during the day and on the days we were closed.
It all combined to work for us as we received compliments from racers about the track's condition.