It's all the agents that leave your lights and heat/a.c. on and doors wide open.  

I see 300-500 per door monthly with an investment of around 20k. 

I have 8 years under my belt with re investing and 10 doors to show for it, all in california!

How should I calculate a for doors to income to know roundabout what my goal should be?

So have your LTR tenant sign a separate document acknowledging that they realize there will be transient guests next door.

that we’ve learned in our 24 years, managing almost 700 doors across the Metro Detroit area, including almost 100 S8 leases.

Needs new flooring indoors in all areas (4 bedrooms, entrance way, hallways, 2 bathrooms and kitchen, 2 new windows, and 3 stand alone ac units for kitchen) Needs kitchen remodel, 1 possible new bathroom remodel.

We manage over 300 doors in Little Rock, Arkansas.  

You have to just commit to doing the lead generation 5-6 days a week (social posts, door knocking, talk to people you know, talk to people you don't know, host open houses for agents in your office, drive for FSBO's, etc) until you have planted so many "seeds" that they result in business. 

My goal for wholesaling is to get my foot in the door of real estate investing without the need to put down thousands of $$$.