. - How does my HELOC factor into my calculations below? 

ideally, you should have a minimum threshold for both though.

Ideally spending under 800k.

Now, my DTI puts me at a place where it'll be close and I'm not sure how my current rental's income is factoring into adding anymore income for me.  

Cash is not the answer as it is not a factor in the HUD process.

As you're aware, with joint tenancies if someone leaves the other individual/s are liable for the rent and should ideally inform the landlord and also try their best to find another room mate. 

If anyone locally would lilke to connect and help me help them I would be willing to connect and show you what i get from the sellers i deal with.   

Cash flow would be ideal, but for this particular property I’m most concerned with the location being one we’d want to live in (A+, A neighborhood, ability to find renters, needs cosmetic work but still liveable, and at least break even (not counting assumed appreciation).

There are also liability issues, privacy concerns, and asset protection factors to consider.

and you might say working in the mortgage dpt gave me the idea and other factors too.