With the Chicago Cubs trading hands recently it seems like a good time to revive a fantasy that almost everyone within the sound of my voice will have had at one time or another. Let's say you invented the ultimate Froobwazzit, the item that no respectable person could be without. $25 a pop retail, $8.50 in profit to you for each unit sold...lo and behold you now have a couple billion in hand. Lucky you. Meanwhile Paul Allen decides that a Peruvian lacrosse team would be more his style. He sells his posh digs, hops on his yacht, and moves to the Southern Hemisphere. On his way out he tosses you a set of keys to the Rose Garden, you toss him a $350 million check, and you are now the proud new owner of the Portland Trail Blazers.
So what do you do in Week 1? Absolutely anything is open to you. Obviously you can't enact things that take undue cooperation from people you can't control. You're bound by NBA rules, including and especially the cap. No stealing LeBron James. But if you can talk about players, free agent offers and trades, management, the arena, or any other aspects of the organization that the owner has reasonable control over. This is your big chance.
If it were me, I think one of the first things I'd do is sit down with my key basketball management folks and make sure Nate McMillan was their coach of the future. If so I'd probably do what it took to make that happen. I won't go much farther than that because I don't want to pre-print your ideas. This is all about you, New Owner Person.
As a special bonus though I'll tell you what I'd do with some of the remaining 1 billion, 650 million bucks. I'd get an exclusive condo in Portland where I'd stay in-season. My vacation home would abut a private cove in Maui. Then I'd have a third residence on a ranch somewhere in rural New Mexico or Arizona. On that ranch I'd house a magnificent telescope, as big as I could get built. I'd also have my own personal waterpark with huge, elaborate slides. And none of this sissy "deposits you gently in the pool at the end" stuff. Most of my slides would end abruptly with an uphill section. If you can't assume cannonball position in the time between exiting the slide and hitting the pool you can't ride it. Friends would be welcome, within liability limits.
If you also wish to elaborate on a couple non-Blazer uses for the money that's fine. Do remember to keep it semi-family appropriate.