My three questions:1) Should I require each adult to complete an individual application, with that application including a section to list other adults who will be residing there?

Paid-off houses is just moving assets from higher risk (and thus higher reward, i.e. you have a leveraged house which frees up cash to buy another house, increasing your return but also adding some risk) to lower risk (if the place goes vacant for a year, you won't lose it to foreclosure, for example).

State farm lets me do the commercial umbrella and keep original personal policies, but I have to increase the liability on each of the individual policies to 500k from 300k, which will add to each policy.

Because, in all honesty, after closing and you set up your recurring payments to pay the note every month, you may never interact with that individual again. 

I know this will vary for the individual and the type of investment, but it seems most are happy if the mortgage is covered and it cash flows some minimal amount.For an STRP, its not completely passive as I would be hiring someone to handle the listings/cleaning but its much less work than the business I own.

I did do a few deals in real estate for other individuals.  

Ut was a small reward but mire than what i started out with.

I'm buying a 1st position NPL on a residence in WA state from an individual who purchased it from a hard money lender.

What said agent acting as an agent and a undisclosed principal.. all those types of issue that can get a broker into hot water.So your probably right your broker given your experience  lack of generating revenue for the firm did not like the Risk = reward component of your hanging your license with him.

It was a 3br/3ba individual lease with separate entrances.