I'm new to BTC. I have read much and i'm currently done verifying my localbitcoins profile. I do have some questions before i start trading:

1. I notice the traders sell bitcoins slightly higher than the market price. (In my currency the price is now 7800/btc, while they sell it for around 8000/btc) Why is this, because of the 1.5{88c91daedd271a990a10650c05d769cae2765e0603edf30ca95f18704e5748e8} transaction fee maybe? This will be much if i buy 20 bitcoins.

2. When you buy for say 8000/btc, will that be the price be constant, even though the transaction and escrow will not release before a day after when the price have changed?

3. In your experience, how long does it usually take for you to recieve your coins, and how long does it usually take to sell them?