If I pay a portion of rent ($400) to my mother, which goes toward the total ($1,200) to the landlord, what name do I put down? Is the amount paid the sum total?

[AndrewMacking]

We split on the payments for the rent and my portion is $400.

[TurboTaxSusan]

You would put the Landlord's name (or their business name), and you would claim the $400 that you pay for your share of the rent.