Around here a mortgage plus taxes is quite a bit less than rent for a comparable square footage and year of construction. Rent should be more than mortgage as you are paying your landlord's mortgage plus the overhead of renting it out. Even if your landlord has held the property for a long time, they should take out new mortgages and invest the money rather than let it sit idle. There are some markets where the demand to rent is not coupled to the demand to buy, but this highly atypical.