He had bought a big house when he got married.

[Alice Chu]

Please tell me if my understanding is correct.
1. I bought a new house in 2000. It was nice and cheap.
The finished past time “in 2000” can only be used with the simple past.
We cannot use “had bought” or “have bought” here.

2. I have bought a new house. It is nice but expensive.
The present perfect has something to do with the present.
We cannot use “bought” or “had bought” here because they have nothing to do with the present.

3. He had bought a big house when he got married. He held his wedding with Tina in the house.
The past perfect refers to an action occurring earlier than the simple past action.
We cannot use “bought” or “has bought” here.

 

[Tarheel]

1. OK.
2. You will hear people say"I bought a new house " or "I bought a new car" or "I bought a present for Sarah" and they still have those things.
3. I am uncomfortable with your third example. Try:

He had just bought a big house when he got married.