i do inside work also, tend to squeegee all inside.
I always tell customer i charge a bit extra for inside work can be upto 50% more inside i.e £15 outside would cost £22.50 inside i.e in/out total £37.50
I always arrange in/out job for next time in that area or when suits me 1st job of the day i.e 9-9.30am if the customer can't do this then i don't bother!
If i can't do 1st one in the day i don't bother as it will end up costing you money, appointments are a no go in window cleaning imo.
Saturdays are always an option, if i turn up and i have time i have done there and then.
if customer insists in trying to get me to fit in with them rather than be negative i use the term call out charge that usually gets them 1st clean of the day.
as to cleaning method i've tried always, i like to squeegee + i think it makes it look to difficult to the customer, i.e something a bit more complicated than rubbing them over(not saying trigger bottle and cloth dosen't produce good results!)
cheers lee.