Cmon vibe the guy is clearly new and clicking on his name you'd see he's only been on the forums for 5 days.
Materia - I believe it works like this (not 100% sure). On your first generation, up until level 25 (might be 20 or 21 now) you don't pay upkeep on equipment. Once you get over that level you will always pay upkeep on equipment.
I believe the equation is something like, for every minute you have something equipped there's a 7% chance of paying upkeep (not positive on the percent either). But I do know that your upkeep cost is 7% of the item.
Selling items you already bought is a really bad way to get money, as you only get like half (or 1/4 of what you paid for it).
It's obviously your first gen, so I'd suggest going with relatively cheap equipment. Your first gen char WILL be the hardest. Every generation after that will give you 3% more experience with every tick. Also after you retire you can sell your loompoint for over 600,000 gold nowadays, so money shouldn't be an issue (although I'd recommend turning around and buying a +1 heirloom'ed item and making 100-200k gold).