Last year's free agent frenzy offers both hope and caution for NFL teams

NFL teams are set to dole out billions in free agent contracts in the coming weeks as teams around the league hope that bold moves in March will pay off with wins on the field once the season starts.

But in a league with a sharp aging curve and specific systems that don't suit all players those dollars spent don't guarantee success.

According to the Spotrac website, NFL teams handed out more than $3.3 billion in contracts last offseason with nearly half of that money fully guaranteed at signing.

The biggest spenders were far from the biggest winners in the season as signing expensive free agents is typically not the best way to turn around a team.