He worked his *** off for a year to save some money, then convinced his dad to contribute and co-sign.

Other equally contributing factors you want to consider is the properties positive cashflow, asset appreciation over time, debt service paydown over time, as well as hedging your dollars against inflation - all of which make real estate such a great investment especially when you have the right property!

They are all equally responsible, it's up to them how they contribute, in what %. 

Looking forward to getting to know everyone and contributing where I can! 

The notion that slumlords believe their tenants will positively be receptive to living in sub-substandard sht holes while being treated with disrespect escapes me.  

We’re excited to have you here and look forward to your contributions!

Seconding the notion above.

Each deal has contributed to my growth and expanded my risk tolerance.

Florida, Texas, Arizona, and Southern California are leading examples where strong demand, warm climates, and economic growth contribute to steady year-round activity.

Having an open conversation about any possible contributing factors, including outdoor exposure, could help resolve the situation.