Don't know the answers to all your questions but I do know what the best strop is. It's the one you make. Strops are easy to make and just as good or even better than what you might buy. Most of the strops you buy are smooth but I personally like the rough side out on mine (easier to charge with compound and holds it longer). Just glue a strip of good quality leather to a board and you are good to go. Even a web belt makes a good strop and holds compound well. Just glue it down on a board. Leave a little room on the board for a handle and you are good to go.
As far as stones go, you can save a whole pile of money and just buy wet/dry sandpaper. I actually prefer sandpaper to stones for most of my sharpening needs, although a diamond stone is sometimes essential for tough jobs. If you do a little searching around on this forum you will find all kinds of good ideas on how to use sandpaper for sharpening but basically you just mount the sandpaper to a block of wood and you are good to go. If you want to convex your edge (like on an axe for instance), glue a piece of mousepad to the block and mount the sandpaper on top.