I can only partly answer this.
My understanding is that Grants,ect come to about 50% of the costs,but I am not sure about that. From general reading though,there is a cost to academies,despite the grants.For instance,Brentford scrapped their academy at a saving of £M 1.5 per year,and went on the B-Team model.
As for transfer fees received,it is fair to say these have been minimal over the years. Apart from Tim Akinola and Ellis Chapman,I can't think of any others. In the case of Chapman,I beileve we were entitled to ask Cheltenham for a fee-whether we did or not,I dont know.