I also have a deal that I've run the numbers on a hot market where I can make 50k-100k profit after rehab for a flip (I have 3 comps to support this sold this month) or I can make 3k/month in rent.

Pools, hot tubs etc?

This is especially important in a hot market and if a home is a really good deal.

For mold remediation (air quality test in livable areas came back acceptable), sump pump/french drain, vapor barrier and some jack post installation, it’s going to cost me between 12k-16k.

You can also build an accessory dwelling unit (ADU) that's completely separate from the main single family home, but the permitting process in Arlington is a hot mess- my neighbor a couple houses down had his ADU permit take 13 months...so up to you on what's worth your time.

Not as hot of a market at some of the bigger cities, but it's not a small town either. 

These numbers are my opinion and have been compiled from Air DNA. 

I once had a guest come and stay from a camping trip in Yellowstone, and they sent me very nice messages about how nice having hot water and lots of towels and offered to pay a little extra for doing extra loads of laundry. 

Are you in a hot spot -- Highlands, Washington Park, RiNo?

Without understanding the full extent of what you are doing, it can be easy to inadvertently cross some lines and find yourself in hot water with securities law.