It could go something like this:
A 19,500 seat arena is built. 1500 of those seats are sold as mortgages. If the average seat is sold for 200 K then 300 million dollars has been raised towards the new arena. The Maloofs agreed to pay this amount in rent across 30 years in the most previous agreement
see here:
http://sacramento.bizjournals.com/sacramento/stories/2010/01/11/daily46.html
200 K may sound like a lot, however at 41 games per year for 30 years that averages to about $162/game and pre-season and playoffs would be a free bonus at this point. Plus, will $162/game be that much even 15 years into the deal?
I see some wealthy Kings fans doing it. But I also see many businesses and cooperations doing it for their clients and/or high level employees.
That leaves additional costs:
100 million for naming rights across 30 years is within market value I believe.
That makes 400 million and should put us right in the ball park. Many will say that it will cost much more. But the Nets just built theirs in Newark for $375 million (Is Sac more expensive than Newark?) The Amway center in Orlando was built for 380.
Additionally, perhaps their is a balance left over once the Arco site is sold and the loand is paid off.
The Maloofs would get their arena while contributing 300 million up front through ESR. They would then be tenants in the new arena rent free for 30 years in a place with much better amenities, which is what they are after. The city could also include parking revenue to the Maloofs on game nights.
Kamilos could control the arena on the other 320 nights per year and cash-in from concerts etc.