I don't think there is harm in painting over, just knock down, scrape off what you can.  

If you have the courage you can even reach out to the owners by knocking on their door or looking up their phone number, to see if they have any interest in selling. 

It's easy to knock out.

I am not knocking on the flat fee guys, they have their place in the business but you get what you pay for as well. 

The thousands of post cards they send out, agents who send them deals pre-MLS, connections within a bank's REO division, bandit signs, buying lists of pre-foreclosures or delinquent taxes, walking down streets and knocking on doors and talking to people, asking around on social media, relationships with divorce attorneys, eviction attorneys, probate attorneys, etc.

So, we sealed up the doorway and knocked down the wall between the half bath and closet to make the full second bath.I would say to look for house configurations such as this as a good starting point.

The thousands of post cards they send out, agents who send them deals pre-MLS, connections within a bank's REO division, bandit signs, buying lists of pre-foreclosures or delinquent taxes, walking down streets and knocking on doors and talking to people, asking around on social media, relationships with divorce attorneys, eviction attorneys, probate attorneys, etc.

This person will hopefully help you save money and potentially go to battle with you if the Feds come knocking. 

I always knock really loudly, and normally talk as I'm coming up to the door.  

Knocking on the door and talking with the owner / decision maker would be your best bet.