Residential Tenancies (Prohibiting Letting Fees) Amendment Bill is now proposed to commence on 12 December 2018 so that is in effect before the Christmas/Summer rental season.

The bill would amend the Residential Tenancies Act to prohibit the charging of letting fees, or any other fee charged to a tenant, in respect of charges for services provided in relation to a tenancy.

Bolitho does not charge a tenant letting fees already.

You can read the whole thing on the Government website:
https://www.parliament.nz/en/pb/bills-and-laws/bills-proposed-laws/document/BILL_77655/tab/digest