Obviously cost is going to vary wildly depending on location and grade of the restaurant.
For 2 we would have
Mixed starter for 2 (seaweed, mini spring rolls, prawn toast, spare ribs, chicken satay)
One rice or noodle dish
2 mains
Prawn crackers.
If there are three of us, it would be as above, but with starters for 3, and probably rice and noodles.
If 4 of us, as per 3, but starters for 4, and add another main.
We always, always have leftovers when we order chinese.
For Indian, we order a main, half a rice, half a naan and half a side each. If there was an odd number of us, we'd round up the rice/naan, but probably round down the side dishes. We rarely have leftovers.
Cost wise, Chinese tends to be more expensive than Indian.