Here are the sentences you've provided, with some minor corrections for clarity and grammatical accuracy:

1) They will have had the ABC company build my house by the end of this year.
2) They will have to get someone to see.
3) They had gotten little boys to climb the chimneys to clean them.
4) I had my tailor make a complete suit.
5) People must hand in their weapons.
6) He's dangerous. They should have someone watch him.
7) They suppose that Brown sold the house.

If you need any specific revisions or further assistance with these sentences, feel free to ask!