People who take on buy to let mortgages in order to make money are being warned to declare all of their earnings to the Revenue or risk being fined or investigated.
Her Majesty's Revenue and Customs has stepped up it's efforts to ensure buy to let investors make adequate tax payments on their profits.
Andy McQueen from Nationwide warned, "HMRC can use stealth tactics to find information on landlords who may not have declared rental incomes".