Since this is two separate buildings, you loose some efficiencies of scale.I usually figure 8-10% vacancy, but this is market specific.You should figure in management at 10%, even if you plan to self-manage at first.What about shared utilities?

The developer can front load a few fees going in to get paid right away but is small compared to the risk factor.

Just curious as to what the best way/most efficient way to connect with real estate brokerages. 

I hired a professional management company and more than made up the fees I paid in efficiencies and spending my time elsewhere.

What alternatives are there to make a more cost efficient heating system?

The risk factor is considerable when you have little confidence in a specific sales price. 

Just because you  start small for your first deals does not mean tbat is where you have to stay. as you make money and learn you will be able move on to a larber multi familt project with much more efficiency than if it was your first.

(There are also operational efficiencies with a larger property too, which is another consideration.)Thanks!

Also, anybody have any tips to be as efficient and quick as possible when building your portfolio?

@Armin Nazarinia someone can operate a flipping business out of an LLC but many times it is more tax efficient to do it in an S-Corp.