He sold some gas rights for $1.75 billion prior to buying the Bills. His net worth was pegged at nearly $4Billion prior to that sale. Essentially the sale he made while bidding on the Bills was enough to buy the Bills and Sabres in cash, with nearly enough leftover to build harborcenter.
NFL teams make $$ hand over fist. The Sabres also do pretty well.
My point was that prior to that sale everyone thought he'd be dipping into his $4 Billion fortune, then out of nowhere he came up with a fresh $1.75 Bil cash.