We also offer an 8 weekly service which attract a 25% surcharge due to the windows being dirtier and the extra administrative overhead.
Yes you can skip 1 or 2 cleans a year if required. Please note however your charge is calculated on an undocumented number of cleans per year. For example a 4 weekly service would expect 13 cleans per year (52weeks/4). The more frequent the clean the lower the price. If you cancelled frequently then you would be on the wrong pricing plan and your ongoing charge may need to be increased. Please note wet weather or not being home would not be valid reasons to skip a clean.