Its one of those things in life tho. You can never find a good one for years, and then 3 come along at once! They never do the inside. Mostly they come when you are out and put a card thru. We've persuaded ours to do us every other month as we couldn't afford every month. We have a 4 bed detached which has 6 windows and a full glass door downstairs plus a small conservatory, and 5 windows upstairs. Ours charges £10 tho we were quoted £15 by another. Think it pays to ask around and keep your eyes out. At the end of the day, they get to see in your house on a regular basis and know if you are at home, so recommendation is probably the best way to go.