As a beginner I don't think you need anything more than a level 3 PR manager. I actually don't think it's common for any user to have more than a level 3 PR manager, but I could be wrong. The crowd involvement specialty is a must. Cheap salaried level 3 PR managers with the crowd involvement specialty are a dime a dozen. An $8-10k salary PR guy can be had for $10k or less.
You shouldn't concern yourself with the fitness specialty at this stage for your trainer, as you shouldn't be overly concerned with the minimal effect the specialty has on negating stamina drops for your current cast of players (your current players can all be replaced, as with most/all new teams). I just saw an $11.7k salary advanced trainer with no specialty sell for $37k - so something like that is what you could shoot for. That's probably a good deal. The next available advanced trainer with the fitness specialty has a $12.4k salary, has already been bid to $60k, and his listing ends in 11 hours. Pocket the money and acquire some trainable players. 18/19 year olds with decent attributes and allstar+ potential is a starting point.