I like to check loopnet for going lease rates to run projections in the absence of better data.

My husband and I found that checking outside our usual circle of family bankers and big name mortgage companies ended up saving a lot of money on fees and rates. 

I also like the idea of a longer mortgage term because it shields you from interest rate and inflation risk for a longer time, and of course you can always pay down your principal faster if you'd like, so I'd look for a 30-yr fixed.  

What are expected vacancy rates for office space over a 10 year period. 10 spaces about 1k per sq ft per unit San Diego CAThis is a Class C well maintained in the Poway area off the beaten path built 1972 

Some neighborhoods of DC actually went up in value during the housing collapse including Shaw, Petworth, Brightwood, Trinidad.A much more likely scenario than a market correction is prices continue to appreciate, and interest rates continue to rise.

Trump this year has reduced the long term capital tax gain rate to a great deal.  

The tenant may withhold the difference between the old rent rate and the new increased rate.

Success rates with collection agencies are extremely low, probably around 10 - 15%.In both cases, you are unlikely to get any money.

In addition, once you've freed up your equity in your current home and invested it in income-producing real estate assets, consider applying for a couple of FHA multi-family property loans (4 units or lease) which have competitive rates and low down-payments (3.75% at the time of writing this). 

Rates are higher than conventional but there are perks, like the fact that they don't require proof of income/DTI, lend to LLCs, and close quicker.