I'll try to answer each question in order...
1. The flooring today is made in batches,so it's recommended you get all you need now. There is slight color change in different batches and a lot of them get discontinued. You can get all you need for the Kitchen and dining room, and later work your way into other rooms, whole rooms at a time.The color difference is so slight that it won't be noticed in different lighting. You may want to intentionally change the color, just to tone down a room or lighten it up. I've put in many floors and my customers have been happy with the results. when you buy your flooring remember to buy a box or two extra, as accidents do happen and you won't have to search everywhere for replacement pieces.
2.Most of the products out there now don't need mopping, just a swiffer or a damp towel or mop.
3. Installing is easiest in a warm dry environment. Clean the sub-flooring and roll out the sound and moisture barrier. Remember these are floating floors so leave the proper gap around the perimeter for movement.
Shop around and good luck.
And Yes use pinsol or enything else ( sparingly ) as the Pergo is pretty tough stuff. Clean up dog pee and other spills a.s.a.p.
Installed over 80 floors, Hardwood, Laminated wood, Tile, Industrial Vinyl, but refuse to install Lenoleum.