If they are within the property no problem (curtains and blinds are) the only issue MIGHT be if it affects the appearance of the lot from the common property. But as you say others have different window covering you should be ok.
If they are within the property no problem (curtains and blinds are) the only issue MIGHT be if it affects the appearance of the lot from the common property. But as you say others have different window covering you should be ok.