I'm trying to convert my portfolio to such properties but don't want to have a high concentration in one area.

I am looking at doing a conversion of an existing 6,000+ SF residential property (currently used as offices) and converting it to multi family (6-8 apartment).

And open to converting it to short term rental if it's ideal.  

Would I be better off leaving my current home alone (to pay it off sooner) and investing in 1 rental property with my $40-$50k or would it make more sense to pursue a cash out refi, convert back to 30 year mortgage, and see if I can purchase 1 or even 2 investment properties with the extra money? 

To answer your question Mr OP:Here is what my lead gen looks like:Cost /Deal $0No mailers, No PPC, No D4D, 100% Hands-free, cost/lead (never look at this metric as it is a useless metric) still is 0SEO of course.We convert 1 every 3 walkthroughs into a deal if Jess goes tot he walkthrough alone.

Increasing Square footage adding a room/bathroom converting garage into a bedroom adding an ADU or mother in law suite. 

It has two living rooms and one of them can be converted into a laundry room and another bedroom.

We found an incredible property in Denver that we could convert to half office/storage for my business and half STR. 

This property is unique as it was originally separate buildings that were eventually combined and then slowly converted some of the space into residential living space.

One is to send them something directing them to your website where, if you have done a good job, they will convert.