The cost can vary hugely. Buying from somewhere like Natural Instinct, where the ingredients are of a quality that could be fed to humans and the meat/veg/herbs etc. mix has been done so that it's effectively a complete raw food bumps the price up considerably. I use Natural Instinct some of the time and even buying when they've products on offer works out at about £1.60 per dog per day.
I also buy from Nurturing By Nature
http://www.nurturingbynature.co.uk/ and use a variety of their foods including chicken carcasses, various raw meat and bone mixes, fish and blitzed mixed veggies. It works out at about 65p per dog per day.
I buy hearts, liver, chicken wings and various other meats from supermarkets and local butchers and that cuts the cost too, but I've never worked out the exact amount.
I don't have a seperate freezer but use the bottom compartment of my household freezer. I'm lucky enough to be able to store some in a friend's freezer as well but for me the biggest inconvenience is having to buy fairly small amounts regularly rather than bulk buying.
It's definitely worth the effort though, as William's coat, skin and general health have improved so much since I switched him to raw.