So for us, we have the benefits of economies of scale and we're delighted to pass those on to our borrowers.

What are some hidden pitfalls (if any) with larger scale investing ?

Yes the end of January is our time scale, although if we got the offer we want, then we would sell it fast for cash before that time period.

When you move up scale to "aspirational" future owners you'll be in a whole different business model and level of "problems".  

My partner and I are starting to scale up (we have two more offers in right now that are awaiting seller response) and while I'm nothing like an expert in this I'm learning a lot and I'd love to have another friend to learn along with.

Where would you focus the majority of your time in order to grow and scale effectively?

I've studied Atlanta for 2 years vigorously prior to moving here and was able to scale quickly with the right partners.  

However we buy in the lower end of the scale.

Good luck The three I came up with seem to be reputable and are operating on somewhat of a large scale.  

I have never rehabbed on such a large scale because I believe I would be inclined to sell it instead of renting it out, but then I risk being taxed at our ordinary income rate if I cannot properly set up a 1031 exchange in time (never did this yet).