It seems you need help with rephrasing sentences using the structure “Subject + have + something + done.” Let’s go through the sentences:
They will install a new alarm system in our office.
We will have a new alarm system installed in our office.Someone repaired my car last week.
I had my car repaired last week.Someone is making Susan a dress for her wedding.
Susan is having a dress made for her wedding.Someone cut my brother’s hair.
My brother had his hair cut.Someone cuts the grass in my garden once a month.
I have the grass in my garden cut once a month.Someone has repaired my TV set three times this month.
I have had my TV set repaired three times this month.Someone is installing a new telephone for me.
I am having a new telephone installed.Someone brings the shopping for my mother.
My mother has the shopping brought for her.They will fit a new carpet in my bedroom.
I will have a new carpet fitted in my bedroom.Someone must inspect our bathroom pipes.
We must have our bathroom pipes inspected.They’ve just decorated my sitting room.
I have just had my sitting room decorated.Someone took out the tent in my yard yesterday.
I had the tent taken out in my yard yesterday.Someone should paint your bedroom.
You should have your bedroom painted.Someone looks after my garden when I’m on holiday.
I have my garden looked after when I’m on holiday.Someone corrects all his speeches previously.
He has all his speeches corrected previously.Someone checks my car engine before I start my journey.
I have my car engine checked before I start my journey.
This structure emphasizes the action being done for the subject, often indicating that someone else performs the action.