According to Clause 2 Article 11 of Circular No. 92/2015/TT-BTC
in case a company buys an apartment for a foreign expert’s stay during the period he/she works in Vietnam, if the agreed salary does not include house rents and the Company takes responsibility for arranging lodging for the foreign expert, depreciation costs, charges for electricity, water and associated services (if any) shall be accounted into taxable incomes of the foreign expert.
These expenses (depreciation costs, charges for electricity, water, etc.) shall be accounted into taxable incomes corresponding to the period the foreign expert actually uses the apartment.