Some developer-owners are building multifamily to the Passive House energy standard, paying tenant utilities, charging as if energy efficient, sending a tiny fraction to the power company, and banking the rest.

It doesn’t really check the boxes of an efficient rental property (less than 1% rent to value, low cap rate, tied to an HOA, etc.) however it performs well in that I cash flow positive every month, it’s new and doesn’t require much (if any) maintenance yet, and my tenants pretty much never bother me and keep the property in really good shape.

I'd just keep the oil boiler and focus on system efficiency.

This is VERY common as more houses get high efficiency windows.  

But it was a lot of wasted time and energy on people who wanted to sell me deals I didn't want to buy.

I've found a few driving by, but I'm wondering if there is a more efficient way of doing this.

Another way is to pull a cost efficient list of absentee owners from listsource.com searching for the quantity of units you're looking for.

Then after closing we replaced the old oil furnace with efficient gas furnaces and separately metering the heat it increased the CAP Rate overnight and made it now much better than the averages in the area.  

Some kind of usable outdoor space.Cost/effort of upkeep: Reasonably efficient utilities.

I want to invest as efficiently as possible.Background: Our strategy is to build up a few rental properties in our portfolio while we are young.