The pros and cons of collective housing

I'd like to write an essay about the pros and cons of collective housing such as apartments or condominiums.

I think there are two advantages of collective housing.
Firstly,collective housing can give us the equal area to live more cheaply than independent houses. For in the case of collective housing many houses own a piece of land jointly.
Secondly,collective housing is more secured from thieves than independent houses. In the case of collective housing, it gives us security agaist thieves to lock only one door strongly.

But collective housing has two disadvantages, I think.
Firstly,residents can't keep pets such as dogs or cats in collective housing. So they can't get comfort from pets.
Secondly, residents can't make a garden in collective housing. They can't enjoy planting trees and flowers.

In conclusion I think collective housing has two advantages and two disadvantages. And I am for collective housing because of it's simple and easy security. Thank you.