You may want to update your information regarding the "Nex n SS" fc, as it has recently changed to the "Nex and SS" fc.
All very useful information though, great tips for the average player.
"So to do the "buy/sell" test, I need to put in a buy offer for 1 cannonball for say 15% more than GE price and that will give me the lowest selling cannonball? I then sell it for 15% lower than GE price and I sell it for someone paying the most? "
This is correct.
"What if my 15% I tried to buy it for that is over the GE price is the same amount someone else is trying to sell their cannonball for? "
That doesn't matter, unless 15% over is actually the best offer in the GE at the time. The GE always gives you the best deal when you instant buy or instant sell something. If I bought a cannonball for 1b I'd still buy it for something like 250gp...unless, of course, the least expensive cannonball in the GE is selling for 1b but this is simply not going to happen.
"how can me buying it for 1gp more save me money"
By beating the previous best offer in the GE by 1gp, you now have the best offer in the GE. So whenever someone else instasells their cannonballs, they'll go to you, instead of the other guy. When you've reached your limit you can turn around and sell them right under the previous instabuy price so that any time someone instabuys cannonballs they come from you.
An epic guide Ringeh.
Been itching to try me hand at flipping again. Just hope that THIS time around I'm successful lol.
Will certainly be referencing your guide tho!