This is a very real senario Lakey91. You have 2 options
1. You use a LTI trade and only get the benefits of their scoring ability and NOT the value they make in monetary terms, if you want to get the value of the price increase you use option 2
2. You use 1 of your 20 trades to buy beams and then you can have the value of his price increase and trade him out when it suits you.
If you want a cash cow, buy the cash cow. The LTI is purely to cover for you instead of getting a 0 for a period of time, not to make money to upgrade.
For instance, if you have Raines, you could use a LTI and get Presti

eek

and get 30 - 40 points or you could buy a Petrenko/Suban type of player. If you went with Petrenko, you would pick him knowing that you would NOT profit on his price rise.
You would not be able to trade Raines to Geary as a LTI. A LTI would only be able to be used for a rookie or a sub 140k-150k player. Once you get the LTI, you cannot trade them out. They will be removed automatically by VS when the 8 weeks is up or when your player comes back.
It adds a new dimention to the game and it does happen in real life anyway but it gives you something to think about