Check in with @Joseph Chiofalo he's a FL mortgage and RE broker and can point you in the right direction for a local RE broker.

Yes you can get a HELOC on your primary residence even if its 2-4 units it depends on the bank.Try a local credit union because some banks or CU's will only do them 1-2 units, but there are ones that open HELOC's for 3-4 units too like BECU.org.

Partnering with Seth Choate provided valuable local insights, making this an attractive and strategic investment for Partner Driven.

The best thing I can suggest is to call around to local banks in your area (at least 3) and ask them if their bank can do this for you. 

Partnering with Graham Lyster provided valuable local insights, making this an attractive and strategic investment for Partner Driven.

Hopefully some locals will comment with more specific information to your area. 

Check with real estate agents, BiggerPockets Marketplace, and local real estate groups for properties.

They didn't go in depth as to what exactly that meant but it's safe to assume they want to help a local family make it their primary residence.

Go to BUILD YOUR TEAM at the top of the screen and look for local investors or meetups in your area.

No clue, underwrite some deals and find out.https://www.affordablehousing.com/ is a website dedicated to section 8 rentals and may provide some insight as to what you can expect to get in your local market.