In today's market an "affordable" home is not so much determined by sales price as it is by the financing which translates that price into a monthly payment. A house hunter's first step is to set a housing budget, then go shopping for the house (price) and payments (PI.T I.) that fit that budget.
Even though there are many ways to qualify to buy a home, make sure the monthly payment makes sense for you. A current rule of thumb is that the monthly payment should not be more than 25-33% of gross monthly income. Restrictions will apply for smaller down payments.