Gift of main residence - payment of market rent

I have a client and his wife who are considering a gift of their main residence to their adult children (x2). They fully appreciate the need to pay a full market rent, in this case c£35k p.a.

The question I have is whether the market rent can be “net” of the ongoing annual running costs/repairs etc. For example, the client estimates that the annual running costs of the property are c£25k p.a. Can the client and his wife pay the balance of £10k to the children and will this be sufficient to avoid a gift with reservation?

Or, would the alternative be for the children to open a joint bank account into which the £35k would be paid and for all running costs to be settled from that account.

Any comments would be appreciated.

Neil Byrne