Hi Editrix,
Thank you for your question.
A Deed of Assignment is not applicable.
To split the rental income in unequal share, both parties must have a beneficial interest in the ownership of the property. This must be done by redigesting both parties on the property Deeds and to submit a Deed of Trust signed and witnessed accordingly to HMRC.
As regards the expenses question.
The expenses incurred in maintenance of the property will share equally in accordance with the split of unequal shares. Therefore, if the property income is split 10/90, the expenses with be treated the same way. Furthermore, if the property is held under joint ownership of husband and wife, Form 17 must be completed.
Further information can be found on our website:
PIM1030 - Introduction: jointly owned property & partnerships and
TSEM9842 - Property held jointly by married couples or civil partners: Form 17 rule: introduction.
As regards the residential finance (mortgage) cost. They must be set against each property that they cover; you cannot set the two properties residential cost (mortgage) against only one property. Therefore, if you are in receipt of income from one property, the residential cost must be included in your accounts for that property.
Thank you.