When my husband, Jeff, and I were in the market for our current home, we took the steps you usually do to make sure we could jump on our dream home should we find it. The biggest part of that was getting pre-approved for a mortgage loan. After submitting all our information to the bank, we got back an approved loan amount that was frankly shocking. There was no way we could afford a mortgage payment that high. What were they thinking?

The amount of loan that you qualify for and the amount of loan you can afford are two different things. In expensive housing markets, like Portland, Seattle, San Francisco and others it’s tempting to spend as much on a home as the bank is willing to lend you, because your dollar just doesn’t go very far in these cities. But that can take away all your financial flexibility and ultimately your financial security.

You may be thinking if a bank is willing to lend you the money, you must be able to afford it. But the bank doesn’t really care about your other goals or even your financial security. They only care that you can make the payment, and they have a formula that gives them confidence you can. The formula is the debt to income ratio, and it is the biggest factor in determining how much money the bank is willing to lend you.

The debt to income ratio is your monthly debt payments divided by your gross monthly income (your income before taxes). Banks generally cap your debt to income ratio including the mortgage payment at 43 percent. Other factors like your credit score and down payment will influence whether they will lend the full 43 percent. But if you have a good credit score and can put at least 10 percent down, you will likely be eligible for the maximum loan amount.

Suppose that you and your partner make $108,000 per year between the two of you. You also pay $1,000 per month in student and car loans. Here is what your current debt to income ratio would be:

How much mortgage will your bank lend you? Your current debt to income ratio is 11 percent. Assuming that you have good credit and a 10 percent down payment, your debt to income ratio could increase by 32 percent.  That allows for a total monthly mortgage payment, including taxes and insurance, of about $2,850. The bank will likely lend you around $450,000, using today’s interest rates on a thirty year mortgage of 3.63 percent and average property taxes and insurance rates in Portland, Oregon.  The value of the home would be $500,000.

Can you afford that? Let’s see. The following table estimates your monthly take home pay and how much you’ll have left to live on after all your debt payments.

Your total debt payments take up almost 70 percent of your take home pay. The money remaining after just making your debt payments is less than $2,000. That puts you in a precarious position. If either you or your partner loses your job, you won’t be able to cover all your payments.

The size of your debt payments drive the size of the emergency savings you need to set aside. You won’t be able to reduce your expenses if you lose one of your incomes with payments like these. If both you and your partner make about the same amount of money, you will need to have at least $8,500 in emergency savings. You’ll need even more, if one of you makes more than the other. You should also have enough additional savings to cover your health care plan deductible.

But even if you have emergency savings, the payment is more than you can afford. You will inevitably have maintenance and repair expenses on the home you just bought. The more expensive the home, the larger those bills will be. Some of your remaining income will need to be set aside for that.

A good rule of thumb for maintenance and repair is $1 per square foot. In Portland, a house in this price range will be about 2,500 square feet, so you would want to set aside $2,500 per year or $208 per month and hope nothing needs fixing right away.

This example assumes you are saving 5 percent of your pay for retirement, which isn’t nearly enough. The longer you wait to save more the greater the portion of your income that will need to go to savings. If you’re still in your twenties, you can get away with saving 10 to 15 percent of your pay (around $1,000 per month). But if you are in your thirties, and don’t have current retirement savings, you should be saving 20 to 30 percent of your pay (more than you have left).

And what about your other financial goals? There is no room for them, whatever they may be. With this mortgage, about all you’ll be able to do is make the payments.

Instead of letting your bank tell you how much you can borrow, you need to figure out how much you can afford while still working toward your other financial goals. To keep your monthly obligations at a more comfortable level, your total debt payments should be no higher than 25 percent of your income.

With the income in the example, that allows for total debt payments of $2,250, and a mortgage payment (including taxes and insurance) of $1,250. That translates to a mortgage of $206,000 and a home value of $229,000 with 10 percent down. That’s just a bit more than half what the mortgage company was willing to lend you.

To estimate how much loan you can get away with given the payment you can afford, try this loan calculator. This calculator only provides the loan amount, and doesn’t include taxes and insurance, so you’ll want to leave room for those. However, it’s a good place to start.

Houses are expensive. Their true cost is much more than the monthly mortgage payment, and you have other goals beyond owning a home. Controlling your housing costs is one of the best ways to ensure you can meet those other goals. Base the house you buy on what you can afford, not what your bank is willing to lend you.

Image courtesy of dfrsce at FreeDigitalPhotos.net