Even if the loan is non-recourse (OP is not buying in a non-recourse state), there are numerous downsides to walking away from the mortgage such as the credit rating hit, difficulty getting loans/mortgages for several years, tax consequences which can include underwater amount, possible influence on hiring decisions, harassment and stress, the awkwardness of needing to move out at what may be an uncertain time, etc. It’s not a good place to be for a young person.
It’s a great skill to be able to fix things yourself and spend weekends on home projects, but nowadays it’s common to instead just call “the … guy” and have him deal with it. I’ve known home owners who didn’t even own a screwdriver. I painted the exterior of my house a couple years ago. It was so unheard of for a non-professional in street clothes to paint their house in my neighborhood that I had the police called on me at least 3 times, with people driving by reporting me as a burglar.