I can only help you with number 5.
You do still go through the process of acclimation. I like this article:
http://www.fishlore.com/acclimating-tropicalfish.htm
You can put the store water removed into a separate container. That's what I usually do. Personally I like the drip method but it can be kinda time consuming. If you ask the store where you get your fish what their ph is it you can determine if there's a big difference between yours and theirs and whether or not the drip method is needed.