Many people looking for homes in the Irving Las Colinas area have mistakenly taken the number they were given by their lender for the amount they were pre-approved for and used it as the number for the price of home they believe they can afford.
There usually is a difference between what you can afford and what would be a comfortable payment. You need to find the balance between what the maximum you qualify for and what you are truly comfortable in paying.
The most conservative way to figure out what you can afford is to figure out what payment would be most comfortable for you and then see what you qualify for. If the number you qualify for is above what you feel comfortable with, I suggest go with the latter. Better safe then sorry.