TF2 Keys Question

Yep, it's the Mann Co. Supply Crate Key. It works on Steam like cigarettes in prison.

1) Yes, TF2 key = Mann Co. Supply Crate Key
2) If you buy Keys from the Mann Co. store you have to wait 7 days until you can trade them (unless they changed it, not sure)
Anyway, you should buy TF2 keys from the market place instead, they are cheaper and I'm pretty sure you can trade them immediately
3) TF2 keys are used for unboxing TF2 crates with a chance of getting a valuable unusual hat. They can also be sold on the market place for Steam wallet money. And remember that there are regional prices for Steam games.

I think this belongs on Steam Trades and not here, but what TheDopefish said was correct nonetheless

For general valuation set by the community so you don't get ripped on on item trades go to: Backpack.tf

i managed to get a crate 50 timed drop :)

I wish i had not opened and traded the items i got from 3 crate 30's for 2 unusual hats. Looking at what the items fetch now i shot myself in the foot i think.

I'm gonna give you a brief example why tf2 keys are being used in trading, it's because of regional pricing. Here's an Example

Antichamber was on sale for 10$, unfortunately, CIS people can get it for 6$. Since it's not region locked, they can trade it to everyone. So they ask for 4 keys (equivalent to 8$ in steam market (for them) or ~9$ for the buyer)

they get a 2$ profit(market) or 40~80cents profit if they want to convert it back to paypal

If we consider paypal, then you can have a better trade (((1.6$x4)+0.30)*1.029) = 6.9$ (0.30 + 2.9% goes to paypal) by buying the keys through paypal. But seeing you got 0 rep in steamtrades, don't do the paypal thinggy atm

The price in keys you see is not cheaper then the value of the game. Valve may set any price, but it doesn't mean many ppl are willing to buy on that price. Because some games were on huge discount, sold cheap at other stores or part of a bundles, their value became very low.

Just for this little chance of getting a valuable item from a chest/crate which can be worth lots and lots of keys(even over 100), people have given so much prestige to these keys. And also people usually buy games during discount and sell em for keys when the discount ends.