Keep in mind comps can change in the 1-2 years you plan on living there.

Depending on market, I would plan to invest 100k in a single family home, find a good property manager, realtor, attorney in compelling market and just start. 

My time here in DC will be likely be less than 2 years so my plan is to do as much research and reading as possible.

The meters, bills, old permits (should be available through the city planning), the appraisals, etc.Most appraisers check with the city on permits and non-conforming use while doing their research. 

There're some alternative planning approaches, but they are always case-by-case.  

A good real estate accountant can save you thousands of dollars by leveraging entity selection and formation, tax deductions, cost segregations, bonus depreciation and tax planning.I recommend finding an accountant who specializes in real estate taxation, business taxation, financial planning and tax planning.You may want to consider working with your accountant remotely to expand your options.I would also recommend looking for a accountant willing to work with you throughout the year.

It has sat empty for the last 20 years but the current owners have completely gutted it, have bids from contractors they're willing to share, cost estimates etc. and have had lots of inspections done and so much pre-work with the city and county to figure out what they can and can't do, so a solid plan is already in place.

All successful plans are generated this way. 

That all is changing now, ever since Hilco Redevelopment Partners purchased the property in 2020, and received concept and development site plan approvals in 2022 and 2023.

I have great relationships with contractors and other trades to do rehabs, so nothing is off the table.