Generally, I'd advise any new manager NOT to buy players for a while until they have a bit of experience with the game. Almost every time it leads to a bad purchase due to not understanding what their team needs really are, or not having watched the TL long enough to avoid wasting the money. Remember the E in TPE stands for estimate. It's a range of sales based off only one skill the player has, so can vary widely. If the player hasn't been trained in multiple skills, or has recently been purchased and is immediately being sold again, then there's a decent chance the player is over-priced.
Generally it's best to get a training program sorted out (there are several thread in this forum on how to do this) as the first priority. After that I'd suggest most teams start upgrading their arena, and only then would I suggest teams look to the TL as a manner of improving their squad in the positions they aren't training. Best of luck!