We're looking for either a duplex (larger lot preferred) or a SFH (3B2B preferred), aiming for a rehab budget of under $50K.

I do these project, but I am going to PM you the contact info for an A/E with a lender that does larger investment projects like this.

This is because rent growth has a much larger impact on cash flow than initial cash flow over a long hold.  

Curious to get some tips from folks that have a larger portfolio (say 50+ units or larger) across multiple MF buildings (so different acquisition dates, financing, etc.) and what software you use?

The larger your portfolio that more useless personal savings become.

A larger down payment is required to cash flow in many markets.

Asking for and evaluating T12 is much more relevant to larger MFR with management than M&P operations. 

With a growing energy and financial industry, Houston continues to attract high-level buyers looking for a balance between urban living and tranquility.Dallas-Fort Worth: The Dallas-Fort Worth region is experiencing a boom in luxury properties.

Quote from @Isaac Ballew: Go to indeed.com or monster.com and look for a job with a larger, reputable property management company.

But, from my personal and professional experience, larger deals are much easier to do than smaller ones.