[spyu]

Just to give you some background on my perspective, I live in Vegas and play poker professionally.
1. You will likely save money if you book your flight and hotel separately. Package deals almost always cost more. Plus if you can get the poker room rate it'll save you a lot. IMO the nicest rooms in town for the poker room rate is at the Venetian. They're all suites and almost all of them have been renovated. You get a lot more space for the money. I have stayed at the Bellagio and Wynn as well and I prefer the Venetian. The rates are $169. You have to put in 6 hrs for each night you want at that rate. If you lower your standards there are much cheaper hotels you can stay at.

2. I don't know what 2-4NL would equate to live I guess 2-5NL. Mandalay actually has a 2-4NL game it's a $500 max buy-in. Venetian has 1-2NL $300 max, 2-5NL $1k max, and 5-10NL no cap. Bellagio has 2-5NL $500max, 5-10NL $1k max, and 10-20NL no cap. Wynn has 1-3NL, 2-5NL, and 5-10NL all no cap. Caesars has 1-3NL $500max, 2-5 and 5-10NL no cap.
The games I listed are the limits that you will find there pretty regularly. Not sure what you're looking to play, but if you're a good player and have decent game selection, I think $5k would be plenty to play at the 2-5 games.

3. The higher end clubs are around $20-$30 for cover. Connections can get you past the line and get in for free.

4. Depends what are you planning on using the money on? Other forms of gambling, clubs? I'd say about $2500.

5. Before I lived here I loved Vegas so it depends on individual taste. I always had to stay at least a week.