Copied this from Grizzlies1982...
Can't refer you to where it is cited but the process has remained the same for years:
1) BEFORE the playoff field is announced, each school which may get in is asked to provide SEALED bids for EACH of the rounds.
2) Each round has minimum bid amount required (about $30,000 first round, with minimums increasing for later rounds). However each school is allowed to bid as much as they wish above the minimums. On the other hand, some schools with low fan support won't even place a bid for fear of losing money on a home game. Either way (high or the minimum) the NCAA pockets the amount of the winning bids.
3) SEEDED teams are guaranteed to always host against lower seeds, and unseeded teams. Thus Eastern WA is guaranteed to host games as long as they keep winning (all the way thru the semi-finals if #1 New Hampshire were to lose at some point).
4) Only AFTER the committee has completed making the pairing in their playoff field are the bids opened. So for those unseeded teams, whichever school offered the higher bid gets to host the game.
It's a crap shoot since schools don't know in advance whom they're bidding against. If Liberty (with its large stadium & fan base) bid just the minimum +$1 they'd be in great shape to host if paired against Morgan State. Yet since they were paired against James Madison (with its large stadium & fan base), whatever amount Liberty bid this year was not enough. We know this because JMU gets to host that one.
Because we have a dependable fan base who turn out for playoff games Montana typically bids well above the required minimums. Though it is unlikely to happen, this still doesn't guarantee Montana will get to host since another school just might offer more.
So IF both Montana & No. Iowa (or Stephen F Austin) were to win their next two games the seeded teams (#4 & #5) who were guaranteed hosting would be out. Then the committee would refer back to the original sealed bids. The amounts each unseeded school bid to potentially host a quarterfinal game would determine where it would be played. If this scenario happened, chances are Montana will have bid more for that possible quarter final and be rewarded with hosting the game.