so - what are the ages of those items, how much will they cost to replace, and how long will they last? 

I decided to ask Rentometer themselves regarding sources, age of data, whether it they are "for rent" prices or "rented" prices (not that they would differ much). 

Meaning, age of guest/minimum stay/advance booking days......?

I’d look into the condo docs once you get them but the age & size of this condo complex make me think those issues are unlikely in this case. 

Depends on asset class and age of property.

@Marty BoardmanThat statistic is so misleading because you were not allowed to foreclose the prior year in many locations.That would be like lowering the drinking age to 18 and saying teenage drinking is up 80%.Foreclosures are at all time lows and will continue to trend up.

There was a time in my 20's that I enjoyed being near all of the lights, sirens, and and amenities that a major metro provides but as you age you start to understand that it's really over rated.I grew up in small town Kansas and have lived in some big cities after I graduated college.

First of all, congratulations on your new career and your decision to invest in real estate at such a young age!

I love your mindset as a young age thinking about his future.

However one thing I didn't anticipate was, while the aged sewer line could easily hand two people living in the property, when my tenants moved in and when the load on the sewer system went to five people, it couldn't keep up.Turns out the line had been damaged over time (orangeburg pipe) and was too narrow, so I had to pay to get it replaced.