I do that, but not so much.
For example, if I'm gonna buy Dzeko (i.e: 25M) Y pay around 15M and then the rest in 48 months.
As the team is paying, I do my best in competitions, so when you win those "500k for winning against *-*-* in the -*-*-*-* cup" the board could pay with that money...
Don't use it too MUCH! if you do it like your friend (paying the 66M in 48 months) you're gonna be bankrupt xD