I tried this a couple of years ago when i was struggling from trad over to wfp.I know what you are saying about the weather,it is hard to commit yourself to regular cleaning when we have customers who look at wfp as a gimmick.
Let me tell you,i soon dropped the idea as i realised that yes the cussies were getting a now more reliable service (ie i would do the free cleans in all weathers) but i was still working my nuts off for free.....NO WAY.
My answer was to go out and build a bigger customer base (much bigger) and tell the customers that they would be on a 4-6 week rota....that way i had a shed load of work and they all got done easily within the time scale they had been told.
I also educated new customers who were sold a wc service on the understanding that their windows WOULD be cleaned in all weathers (excluding hurricanes,flash floods.and oh yes and if i was playing in a poker tournament

)
You have to learn to tell the customer what your business is about.The only downside to having a lot of work and doing it in all weathers is that you do not have the option of being lazy...you have no excuses and have to get out there come what ever.
Do the right thing for you,it is your business make it work for you and good luck.
