I do insides and out no problems.
Do the outsides first, that way its easy to tell where the grime is on the insides.
Last year just before christmas, i was asked to clean some office windows, inside only in London, charged £400 for half a day, used squirty bottles, microfiber and scrim, packed into a backpack and went in on the train. They were so happy, they have rebooked me for this christmas.
Some of these comments are hilarious, about doing insides first and then run before they complain...jees guys. What tds are you cleaning at, bet its not 000!
I have never had aby problems doing insides. Never.
Now conservatory roofs?? Id happily rip it down free of charge..