I understand what Chris is getting at, but IMO, it's not something for investor consumption in a forum.

Windows certainly do add value when marketed well, or when the tenant notices and thinks of it (because they contribute to noise reduction and energy consumption both), however many do not consider this in a home.When a tenant lives in a home and makes a Capital Improvement request like this, you are under NO obligation to do so. 

I had a case of the latter in a ten-unit last week- I got a letter from the water utility indicating very high water consumption(and I treat those letters very seriously!)

Instead, I receive a huge bill every month for sewer that is based on consumption. 

The heat pump water heaters are a good option for energy consumption.

Absolutely no cold water sandwich effect on this unit plus electric kW consumption is minimal given that our highest monthly electric bill was $48 with everything, including the a/c running.

Instead of spreading that cash over 10+ smaller properties, this would limit your headaches and time consumption.

.- According to a study by The Beer Institute reported by BeerInfo.com, Nevada ranks sixth in per capita beer consumption, with residents consuming an average of 35.8 gallons annually.

RUBS is Ratio Utility Billing Services and really all it's doing is charging the tenants a ratio of the water consumption bill. 

The builder wanted to share the power across the entire development before sending any back onto the grid, but the utility fought it and the end result was each townhouse had to netmeter its own electricity generation/consumption to the grid independently.