Invest in cards that will have higher value down the road. Live series 84 golds for TA series 3. Live series power bats for the event tomorrow. Inning 1 exclusive cards that will later gain rarity and value through lack of availability, same with inning 2. Purchase as many copies as you can of all star, rookie, and veteran cards for impending collections requiring these.
Plenty of long term methods. Beyond that, currently buy low sell high. If you have 200k, I'd personally invest in 79 silvers, 84 golds, and 5 copies of every All Star/Rookie/Veteran on the market (gold and below).