There are two types of fantasy owners. There are those who play from season-to-season and then there are dynasty owners; who love fantasy football so much that they need to play all year long. One of the best things about being in a dynasty league is even if you had a bad year, you are never done playing. Owners are always looking to make moves to improve their teams for the future. Right now is a great time for those owners who missed the playoffs to buy low on some younger players that could help their team down the line. Here are four players dynasty league owners should be targeting: Ryan Tannehill, QB Miami Dolphins -- Tannehill has been outshined by other rookie quarterbacks but if you are playing for the long-term, there is a lot to like about the Miami signal caller. Tannehill was thrown into a situation where the Dolphins have one of the least talented groups of receivers in the NFL. Still, Tannehill has displayed a live arm and good pocket presence. Also, Tannehill only started 20 games in college, so while he was inconsistent in 2012, his best days are still yet to come. Rashard Mendenhall, RB Pittsburgh Steelers -- Mendenhall's days in Pittsburgh may be coming to an end after he has been a healthy scratch the last two weeks but at only 25-years old, the former 1,000-yard rusher is far from done. Assuming Mendenhall is healthy next season, a change of scenery could be just what he needs to jump-start his career. In the two years before tearing his ACL, Mendenhall averaged 1,191 yards and 10 touchdowns, so he is a nice buy-low candidate right now in dynasty leagues. Robert Turbin, RB Seattle Seahawks -- There are not many feature backs left in the NFL but Marshawn Lynch remains the epitome of a bell cow. In the last two seasons Lynch has touched the ball 579 times. Lynch is a punishing runner, so all those carries could start taking their toll soon. Turbin looked good in the preseason and in his limited opportunities spelling Lynch; displaying nice vision and impressive power. Turbin is also an excellent receiver, so he could be a big-time fantasy producer if he is called upon to be the starter. Robert Housler, TE Arizona Cardinals -- Some liked Housler as a possible sleeper this year but when a team's quarterback situation is so unsettled that Larry Fitzgerald turns into an average fantasy play, Housler does not have much of a chance. Still, Housler has given owners a reason for optimism over the second half of the season, catching 33 balls for 276 yards since Week 7. Housler is an athletic tight end with good hands, so if Arizona finds a quarterback in the offseason, he could emerge in 2013.