Getting my questions answered...tough stuff.

Ok, I've been working on getting my game to a state of visual appearance (modeling some stuff in 3ds max 2008). But I've been having some difficulty with measurements and such. Here are some questions that I have for anyone who can answer them. Specifically about level design.

1. When modeling things such as a city or building, which measurements do I use in 3ds Max in order to make an entire city to fit into a game world?

2. I need tips on making a semi-futuristic city, but I can't seem to get anywhere researching myself on the internet for references or other types of inspiration. Any ideas?

3. If it were possible, how would I go about getting these answered by a level designer that has worked on an open-world/sandbox game?