But is there a requirement that you need to full fill before making your first post?

Send it by US Mail with proof of delivery required and/or place it in an envelope with their name on it and post it on their door. 

The capital required for Denver, and limited cash flow makes it a tough market to get your next one.

You should require the tenant to carry $100,000 liability.

Most DSCR lenders will require a credit score of 620 or better.

If the property does not require an extensive rehab and just needs cosmetic repairs then a standard landlord dwelling policy in most cases depending on the carrier.

That is why PreREO requires the defaulted note buyer/partner to file for a court hearing requesting a third party independent receiver to be given court approval to accept rent on behalf of the actual owner of record and divert the funds to you, the note buyer prior to taking title via a completed foreclosure.

I may be able to STR a spare bedroom but that would be for later.Background: A fixer upper, but I do not know how much fixing is required. 

Sometimes, buying an existing property can be more cost-effective and less time-consuming and maybe require slightly less permits, etc. 

If not on a state road, a muncipal permit is also usually required.