Because these houses are usually very elderly owners they are usually in very good areas, because they were bought in 1950, 1960, 1970, it's so frequently just a tiny house, decent size lot in a hot hot neighborhood. 

I myself do not totally agree with the word " tiny " Reason : taking some actions is better than no action " delegate the management instead of personally managing "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~From my recent experiences : yes key for large building is to the be person owning / control instead of one dealing with tenants daily issue or simply spending hours shoveling snow. 

It's incredibly easy to boost the ROI with just a lot of tiny, little, tweaks.  

I'm making a tiny bit more money now but really only about 100-150 dollars more monthly.

If you have it properly staged you could show a tiny bedroom as an office, making the buyer miss the size of the space all together. 

Even on a tiny small scale, look at the per-unit costs of Buildium, the more units the cheaper the cost-per-unit.  

A tiny price to pay to hedge your investments.

. - That entire gain is tax free, since it is your primary residence- Your monthly payments will be over 4k per month, but almost half of that is going toward your own equity and the other half is a tax write-off that reduces your taxable income and possibly brings you to a lower tax bracket.SUMMARY: I'm not quite ready to declare victory for purchasing your home in NYC, but I have to admit, I just convinced myself a tiny bit more. 

Prefab/tiny home is definitely not a bad idea, keep the costs down and the cashflow up if you are planning to live in it.

I live 15 minutes away so it isn't a big deal, plus they are all on tiny lots.The duplex we bought last year has tenants responsible for lawn and snow in the leases, but we knew before we bought it that the landlord was taking care of it, and I would rather stay away from providing and maintaining equipment for tenants- to much liability.