A lot of these are just (totally normal/appropriate) inexperience. The answers aren’t super clear-cut, but there’s LOTS of videos/content that address these in different ways and in different levels of detail. In VERY brief:
1. The only reason why it tells you to pick those up, is that they have atleast some potential to be good, allthough they are usually trash. the other yellow bases you see (not highlighted) are the ones that can never be good.
2. This only works properly with uniques. Allthough you need to check manually if it is uniques with a great explicit roll. e.g. ventors gamble, facebrakers, and a few others. those can be worth 100 times more than the cheapest for sale if you are lucky with explicit. regarding how to price rare items this way, in my experience its very inconsistent.
3. It depends what item it is. if its a weapon you basically need high Phys dps, unless its a foil or a very fast claw. in that case stacked elemental dmg and attack speed is also good. you also need to see if there is any open (good) crafts. every now and then you can make a 300 dps sword go to 350 if there is space for attack speed to be crafted ect. if you are lucky to find a 200%+ phys weapon with attackespeed, and theres a open prefix you can craft + added phys, and it will tripple in valvue. this is just the basics. with other things, its usually life + resist. on jewerly added phys, crit multi(for amus) and elemental dmg with attacks, are worth a lot if they are combined with Life. Life is the most important stat.
4. Sounds good. maybe make an elder ring if you can and only farm shaped/elder influenced maps.
5. Umm. browse poe.trade for better understanding of price ranges, and umm just play alot. that works!
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