One of the main things you have to lookout for would be the thickness of the material used for the hammock. This can tell you a lot regarding what that hammock is designed for.
Lighter material usually means they are meant for casual garden use, typical for users who just want to lounge around or use it for afternoon naps. Heavier materials, on the other hand, are designed for more rugged terrains. These hammocks are better used for camping trips rather than home use.