I know a few doggy daycares that are pretty good if you're interested in that route, the idea of doggy daycare is that the dogs gets it's energy out at daycare instead of taking it out on your carpets/furniture etc.
My dogs are left for 9-10 hours (WOW when I did the math, I leave for work around 8am and get back home around 6pm, I hadn't realized it was that long I was leaving them for
) but that being said they are usually pretty good. However if I leave anything on the table within their reach, forget to hide my pillows under the blanket, leave shoes out etc. it's basically considered fair game and it will be ripped up/destroyed by the time I get home.
When we just had the one dog (Oreo) she would pretty much always find something to destroy on a daily basis from being left alone for so long. After we got our other dogs it helped a lot, for the most part they keep each other company. It also helps to walk them everyday, I know when I miss taking them for a walk they usually will find something (mostly paper ie: fliers left on the table) to rip up.
Most dogs, as long as they are potty trained, will not mess in the house and will hold it for up to 10 hours before they would defecate inside the house.
As for crate training I think 8 hours is too long to leave a dog in a create for on a regular basis and you are right, with Edmonton weather, leaving a dog outside for an extended period of time (especially a short hair dog) is a bad idea.
This is just my experiences and my opinion but I hope it helps. Feel free to pm me or call me etc. if you have any questions, and I'll try to help answer them.