If you need a LB, then get Matt Hill from Preston. He costs about 400K at the start and is really good as well. Cristian Pulhac is another good LB but not as good as Hill
imo.
You can get Cristopher Samba for less than 1M (sometimes as low as 600K) if you bid early enough for him. Excellent CB although I think if you're a couple of weeks in, he'll be much more expensive already.
Gustavo Cabral is another CB whose contract is up at the start of the game. Excellent CB.
And then you can loan in Mathieu Flamini from Arsenal. A very good DM he is.
Try Marko Marin as well. Pretty good right from the start. He's an AMC btw but can play on the right wing too. Cheap again at 200-400K.