i got a new dishwasher months ago that comes with a sanitize cycle. I am leery though so I have done this method:
I always rinse out my bottles after pouring them. So I fill up a bucket (or 2) with a bleach solution and let them sit for a few hours, overnight, whatever. I them take them out and put them in the dishwasher. No soap, no cleaning agents, nothing. I run the bottles thru the Sanitize cycle with Heat Dry. Leave them in for a while after they are dry, and don't open the door until you are ready to bottle. Because bleach is very volatile, it will all be gone. No bleach stank! I still fill my bottles by hand (22oz only) so I put the bottling bucket on the counter over the dishwasher, and leave the door open. I use a spigot with tubing to fill the bottle, and then next one is right there waiting. Simple (as far as bottling by spigot goes) and can be done with one person.