My dad has owned a few houses over the years, both his own and ones he maintains as investment/rental properties. He has been the best consultant during all this, supportive and patient and willing to listen and to impart his own experience.
Some of the best advice he’s given me: "No matter how much you love a house you see, remember that this is business. It’s not personal. It’s not the love of your life. It’s not that these things don’t matter, but that until that house is yours, you just might not get it. And you can’t let that get to you, because the one that is right for you, and ultimately yours, is out there. This one was close, but that’s all it was."