Have someone dig the post holes to a minimum of 4ft. I live in RockyRidge and built my own walkout deck. There is a reason they call it RockyRidge, It should be called Boulder Ridge Good God poor sucker down the street has a lot full of rocks prior to their house being bulit. You should draw up some plans and pull a permit with the city. At a minimum there is a pamphlet on the city website that has some useful info and rules. I would just ask a few of your neighbors they would have some good references. Those signs are usually a good place to start. Get a few quotes and references and go from there. Cash deals are good but be careful. You have no recourse and if they get hurt while working you could get burned.
http://www.calgary.ca/docgallery/bu/...wood_decks.pdf