Noun phrase or not a noun phrase

1. if we think (the price of an item is too high), we won’t purchase it, and the price will probably come down.

2. if you want to buy (a bottle of water while strolling) through central park, you may be in for a shock.

3. (the same brand of bottled water) you buy at home may cost twice as much in the new york city.

4. how much are you willing to pay for (a pair of athletic shoes), a new phone, or the latest video game?