When you say 20000 and 90000 I assume you are talking about salary? If so, you can get a level 4 for a lot less than that. I got mine at 10k.Personally I would go with the level 4 coach. It will cost a lot less, and unless you have a very very good trainee that is worth it, the extra money you would save going with the level 4 coach would allow you to buy a much better player than the one you are going to train.Season is about 14 weeks long.For a level 6 trainer = 90000 x 14 = 1.26 million + initial signing bonus.For a level 4 trainer = 10000 x 14 = 140kThis is not including the raise in salary as I'm just keeping it simple, but the raise in salary for the level 6 trainer will be more than the raise of salary for the level 4 trainer.I'm not sure what a level 6 trainer with 90k salary goes for these days, but lets say it goes for 140k (just to keep it simple).That means you will save 1 million dollars over a season if you go with the level 4 trainer.The level 6 trainer will probably get you 4 or 5 weeks of extra training per season. 4 or 5 weeks is equivalent to about 3 pops (depending on what you are training).So the question you have to ask yourself is whether you would rather have a million dollars, or those extra 3 pops per player.