Lookt for two things:
1. Unique props. If only one book has it, the line is not as sharp
2. Matcup props, especially versus non-NFL things. Tiger Woods, Daytona, NHL and NBA are common. In a matchup prop, there are twice as many ways for them to screw up.
Seriously, spend a few hours looking at these matchup props. It is worth the extra effort.
1. Unique props. If only one book has it, the line is not as sharp
2. Matcup props, especially versus non-NFL things. Tiger Woods, Daytona, NHL and NBA are common. In a matchup prop, there are twice as many ways for them to screw up.
Seriously, spend a few hours looking at these matchup props. It is worth the extra effort.