One option is to find out of your company (or your spouses ) has a contract with a hotel chain that has a location in Indianapolis . Hilton etc... depending on the wording of the contract they have to honor the contract rate -even during a normal sell out period .
If any of you have a Eli Lily connection you should be able to get that rate even during Gen Con . I know people that did that in 2017 and 2018.
Some contracts are more generous, but in many of those cases, the hotels only have to honor the contract rate if the guest can show the travel was work-related. But, certainly a good thing to try; all they can say is no.
I've never used AirBNB, but apparently some others are having issues with it regarding Gen Con. Just something to be aware of and best of luck getting a place.
It's never to early to start thinking about booking hotels. I usually book an outside of block room the week before the current Gen Con(yes this is kind of crazy)
BUT if you book that far in advance your rates will be below 300$.
MANY people will tell you it's impossible, or you'll lose your room, or blah blah something else.
Those are not factual statements, as a guy who's been going 21 years, booking out of block for around 5 now, it works. Every year.
According to Travelocity, there are no downtown hotels available as of Sunday. Closest hotels are about 5miles away at $2=300.00 per night.
If you check the room rates not during gencon you will find the nearest hotels are offered at twice their normal rate during gencon. Our family policy has always been to rent a room on 465 for a reasonable, non-inflated, rate and commute. The add-on trash fees and taxes we didn't have to pay always paid for our parking and I didn't have to descend into the hell called room reservation. Now that they have gate 10 and shuttles it really is the best way to go unless you have very small children who need naps or extensive costuming.
If you are willing to commute the 50 miles to the ICC, I know an excellent B&B south of Indy for only $100 per night.
If you really want to go crazy, you can rent the motel 6 Jacuzzi suite for $70 a night, but you need to do that at least 6 months in advance (I used to reserve right after Gencon). It is also on 465