Entry fees are no more than normal I'm assuming so the monetary demand isn't much different than a single day bay (its still cool enough to camp, don't spend money on hotel). The only difference is - added money to purse = more entries = more time needed for each event, hence three days instead of 1.
If there is $300-$500 added money to the single events and $500-$1000 added to Two dog events you WILL draw a crowd. Whatever month you chose.
That being said....a mid to late summer bay would ensure that your three day bay is HUGE!
Hog feed must be cheap where you are! You should trying putting on a bay and adding that much extra money. You barely make enough to pay the help , light bill, and keep the hogs in good shape .
Lol, I don't own a bay pen. If I did the money sure as heck wouldn't come out of MY POCKET!!!
Sponsors! Sponsors! Sponsors! Hotels, campgrounds, feed stores, magazines, vendors. A little bit of money from a dozen or so sponsors can add up quick.