There are more effective ways to accomplish this.

At the end of the day, 5% of $80 is more than 2.5% of $100 and the fee models used in the industry will sometimes lead the listing agent's to go from being the seller's advocate to the buyers.

If you only plan on owning 2-4 properties, then there's really no harm in self-funding them unless you know a better, safer way to make more than the going interest rate on that money (most investment mortgages right now are about 7%, maybe effectively 5.5-6% after taxes depending on your brackets and tax structure).

The 1st position heloc has nothing to worry about because it will still be attached to the property after the 2nd position heloc forecloses....death of the borrower has no effect on it.Likely not time to make a deal with the “owners” since that would likely involve probate, and time.  

Biggerpockets folks will advocate for real estate as a long-term investment and I'm no different, but while you're thinking about it, I'd also recommend you consider and research treasuries through treasurydirect.gov while rates are still relatively high. 

I met a young lady on FB really advocating for them.

You've unfortunately unlocked the centipede effect by saying Columbus.

Or because they don't want to be the bad guy.With closing on Dec 4th the issue is that your 28 day notice will be effective Dec 31st and your tenant has until Jan 31st to vacate.

What's the most effective means of dealing with this issue?

Its much more cost effective to outsource things like skiptracing and direct mail.