Between these two strategies, we closed roughly $50,000,000 in volume in the Bay Area.I'd recommend doing the same if you're aiming for a similar demographic.

In my area there will have to be septic tanks and special water/well systems due to high volumes of MH.

There are plenty of local jobs and a high volume of low income multi-units and MHs in fields in the area. 

Unfortunately my results weren't great as I think I should have scaled it and added more volume.  

@Benjamin Poole  No , any discount a contractor gets is due to his loyalty , buying volume and negotiations with the suppliers .

The volume of human interactions is just different here, so of course the spread rate will be lower.All that being said, I don't believe we're in anyway immune here.

(First half of the shareholders meeting notes below)Re-cap of tesla's recent accomplishments by Elon1)  Shanghai gigafactory - DIRT to FULL VOLUME production in 15 months! 

You say you are not rushing, but the altitude that you are displaying in your post speaks volume.  

I charge anywhere from $49-$500 a month depending on the volume of work.

My buddy @Daniel Sisto does a ton of volume on properties that very well could have gone to agents but he works harder than they do, he has better systems, is more organized, and wants it more.