This summer I have received private pms from several folks regarding the contact of advisor/agents for their players.
I figured instead of repeating myself I could give some general information as well as my own opinion on the process.
First, always keep in mind that they are agents. They get paid to represent your son/relative but not until he gets drafted and signs a contract, probably turning over about 4% of the players bonus if he does.
Be familiar with the NCAA rules for amateurs regarding dealing with a professional agent. For your HS player, you should be the person who deals with the advisor/agent, if he is in college he needs to establish his own relationship because they will be making decisions together later on, not with mom and dad. If your son is in college, I do beleive (someone correct me if I am wrong) that an adviser/agent has to be approved by the programs athletic department (same as those for football).
There are differences between agents. All present themselves as advisers but they are agents. You can ask all the questions you would like but there are some (questions) more important than others, that would be what is your fee, what equipment or card deals can you provide for my son, do you provide tax service and guidance from your office, and do you provide financial services (you dont want this) and most of all, do you have at least one player on the 40 man roster? If they do not, that means that they cannot legally represent your son with any team, after he is drafted. Or participate in union/player meetings. This becomes important. The only time my sons agent spoke with a team regarding him after he signed was when he was hurt. Most milb players are led to believe that they have limited choices in choosing their doctor or surgeon or even a second opinion. So if your player is hurt, its helpful if he has someone who can speak on his behalf to the team. Most likely he has had other players that have been hurt, so he knows how to deal with the situation. FWIW this isn't only for milb but MLB players as well. Anyone hear that cardinal pitcher Jaime Garcia and management were at odds about him having another surgery. It happens to everyone.
The way that the draft is structured and the rules, I do not believe that later signs do need an agent. Familiarize yourself with last years draft and who signed for what in what position.
Son did not have an agent out of HS, he had been projected as a 5-10 round pick and most of the guys who came calling aren't even in the business anymore, most had a stable of milb players hoping one or two of them would break into MLB. The agent from a big agency who evaluated son before the draft would not represent him as a HS player but would as a college player (which he did), as he advised attending school first.
Another guy from this area who had the highest paid player at the time went trolling for guys out of HS. I understood why later on, he was the biggest jerk I ever met, he broke NCAA rules with many, he had a player sign an agreement with him before his contract was approved, and that player needed knee surgery, now the player was neither here nor there and lost his D1 eligilbilty at a big FL D1 because of that. He even posted here at one time. Beware. In other words do not sign or promise anyone anything. Sons agent collected his fee 60 days after he signed his contract, just in case something went wrong. If that agent is looking for his money the day your son signs he isn't worth talking to. These are all things that you will need to work out before the draft.
And yes he will most likely not call again unless your son is drafted, and yes even #1 draft picks can get bad advice (IMO).
How do you know that your player even needs an advisor? As the draft gets closer, for many it becomes more and more difficult, that would be for those that most likely, at some point be chosen within the first 10 rounds. If your son gets drafted in a good position with no advisor/agent of record, dont worrk the phone will be ringing!
Understanding where your player fits in would depend on lots of things, position, player in HS, JUCO, college. Also a very big indicator would be a prospect list compiled by PG, maybe Baseball America. They usually get it right. So if your son is ranked #30 in his class, chances are you have had many many scouts maybe even a GM contact you or your son. You might already be asociated with a top agency. If he is a #500 prospect, chances are he doesn't need any advisor/agent, yet.
If I have missed anything please let me know, or send a pm, and please beware of guys promising your player more money, a better draft position or communication with the team on a regular basis, this includes before and after the draft.