The main problem is the risk.

What if the hosue price drop more?
What if some hidden issues with the house need big fixing cost?
What if the tenant is not paying?
...

All of those will eat you gain easily.

You are managing this house yourself, right? It could be easily 100+ hours/year for you to manage it. Gas cost and other headaches. You are actively working for this house and the gain is just the minimum wage.

This is not a passive income for you. And many risks...