Keeping your existing home may well be an option in situations where significant equity exists in the home.There are significant benefits including your knowledge of the area and its rental potential and indeed stamp duty savings in choosing this option as opposed to going out and buying a new investment property at a later stage.Lenders will usually be happy to leave a mortgage of 85% on the investment property with the balance of total borrowings going on your new home.The greater the investment property mortgage the higher the tax relief on rental income.If matters dont work out you always have the fall back of selling the property!