Cuban has sold the Mavs to Adelson-Dumont Family

[Jason Terry]

1 All of what you say makes plenty of conceptual sense.
2 "I wonder when the terms of the partnership will become public " --- Never. No one puts things like that in the public domain unless they have no choice (for example, if one side sues the other). There is no reason to air such legal work to the public, and it's probably all downside for them if they do.
3 I expect the Adelson's will be buying way more than 51% up front. The reports spoke of a $2B liquidation being added to additional cash on hand, with which they are buying a portion of a 3.5B enterprise. I would be surprised if their share is less than 60%. And in time, there may be provisions for them to buy even more (perhaps all) - that's a common setup. Cuban will still have a public face with the Mavs for some time, but FROM DAY ONE he won't really be The Owner any longer, in NBA eyes.
4 When you say " the NBA “business” side of it i think will transfer quickly so they can start paying for what’s needed", I'm not sure what you have in mind. The A's aren't buying the business side, separate from the team, nor could they, as both "sides" are intertwined, and there is just 1 entity, not 2. The A's will await NBA approval to be the Governor, and then have majority partner ownership of all of it (as well as majority responsibility to see the bills are paid, but not sole responsibility).
5 In addition, if you are envisioning a cash infusion on day 1, I'm wondering why. At this point in the season, there's not a lot of opportunity to spend more than they already have on player payroll. It's not as if they are going to unilaterally back up a truck full of cash to put in the Mav bank account.

I guess what i meant on that last part is the A’s could pay for all the groundwork immediately on their own and it be part of the behind the scenes deal. Lobbying money for casino gambling in texas and lobbying money for the arena/casino/resort area? Like you say though, anything that touches the actual basketball side would need to be more transparent and part of the partnership where both sides contribute