Upgrading to legendary

Hello,

My account is @matt1117 if anyonr would like to look. Im investing into mlb and I have a question.

I have the top 10 pitchers and top 10 non pitchers all at common and i will be boosting the pitchers. I also have 11k additional rax saved.

I would like to upgrade aaron judge, Shohei and Yoshi to legendary as investments and im wondering how people typically go about this as Ive never upgraded that high.

Is it best to just buy player packs the whole way? Should I try to buy other peoples player packs for them? How long until I can buy 1 pack per day for these players (right now its 1 per week)?

Any advice would be appreciated.