I'm shocked to see it's the only ad in this area. 

Or at least that's what the guy on the YouTube ad told me.

Can we take out a joint HELOC if only his name is on the deed to the house or do we have to go through the process of adding me first? 

Adding a little more info to your profile will enable you to better connect to people who are most likely to be able to assist.

The entry price point is attractive enough for my investing partner and I to feel comfortable with the added risk.

so I just finished a rehab on a new acquisition and posted my ad to Zillow for 1000/mo which I thought was ambitious.  

Ight now I’m doing some direct mail and posting ads on Craigslist.

This did save money, but it added a lot of time because I bought clearance cabinets, so then had to drive around to make a full set, then I had to paint them...I would have saved time and effort by just buying RTA or mid range cabinets.Time is Money!

This has resulted in 3 credit collection accounts being added to MY credit report.

Assuming you are getting cash out, since you stated as such in your first paragraph, I think this is a no brainer...once you look at 2 numbers:1 - Added cost out of pocket (higher closing costs) for lower payments = $21,0002 - Added cash out with lower payment option = $3,0003 - Total added cost (cash out of pocket) for lower pmt option = $18,000      Note:  This is money you have to recover before you are making any profit...so the added cash flow isn't a plus until this money is recovered.4 - Monthly savings (added cash flow) = $1655 - Number of months to added cost recovery = 109...or 9+ years.