3. Just beacuse you think a name sounds great & brandable doesn't mean it's worth anything! Keyword based domains are usually worth more than a brandable name.
4. Don't get emotionally attached to a name. If your going to sell domains, sell them!
5. Traffic is king beyond all else.
6. It takes money to make money in most cases. Those who make a lot of profit are buying names x,xxx - xx,xxx and reselling them for more.