Friend of ours are considering moving to India and I just sent the couple the following tips/answers to some of their questions and thought it might help someone else out there...
1) Bring a lot of cash. It is more expensive than you think. I'd say savings of $25,000 should help take care of a car, the down payment for rent (Mumbai is a whole lot more), new furniture...
2) Secure school admissions for your child. Have your company negotiate this as they are much better at it than you ever will be.
3) Get a sense of fair-market rents and rates from over there. Sked time with a broker and hit the ground running as soon as you arrive. Ask neighbours about water and electricity outages.
4) Book a guest house. Your employer might put you up in a fancy five-star. If you have a family, skip it as guest houses will be more comfortable and you are less likely to get sick and you will have more space.
5) Find other returnee families. They are a great source of information. They also will help you find your staff from maid to driver.
6) Get on a list of expats, in Delhi, that's yuni-net or Delhinet but each of the Indian cities has one. Also try Craig's List for deals on flats and used furniture.
7) Make a trip to Costco or Sam's Club, even though I make fun of it... A lot of that packaged stuff and sauces are very expensive here. No shame in Pantene, Aunt Jemima, Annie's mac and cheese.
8) If you are being relocated, add about a month to 6 weeks to whatever they say the eta is for your goods. I have yet to meet anyone who has gotten their stuff on time. Ensure your employer does the negotiation for the release of goods and paying any related bribes etc.
9) Assess your electrical needs - laptops, toasters, video projectors, stereo systems. We came with two large converters (if you need the exact conversions, Nitty can tell you) and they were more than adequate. Buy a bunch of the 220- to 110 converters for a dollar each and sprinkle them around the house.
10) The most important thing you can bring is an open mind and a lot of patience. Nuff said.