All require a permit/license.I would definitely point you in Arvada's direction, as they've just put updated regulation into place allowing up to three owned properties to be run as short term rentals. 

Just read the cfpb sitehttp://www.consumerfinance.gov/regulations/integra...

Thanks Tom,There are so many laws and regulations in RE here in Ohio that its overwhelming at times.I send so much stuff to our attorney every week that I dread the monthly bill lollolI don't think this one to be a priority but I appreciate you pointing it out.Thanks for costing me more $$$ as I will probably forward it to my attorney now haha

Where's a good, official place to start researching Maryland's rules and regulations about all this?

I had strict criteria (> 85 walkscore, < 25 min walk to downtown, cash flow positive with a 15 year mortgage after 25% down).

Professionally, my company works with vacation homeowners and property managers across the US - what you describe is something of a black hole where it seems the market just moved faster than the regulators who have been in catch-up mode.

Watch state regulations on those, and your agency laws as well. 

Borrowing money to fund lending operations becomes a regulated lending activity regardless of how much is borrowed or how big or small a loan might be. 

Im curious if anyone in Denver with a small multi unit has experienced this or can shed some light on the process/costs of Denver Water regulations...

I did not take this approach when I started because I definitively knew I wanted to strictly just be an investor.