Its a tough subject because logically, they are joint and several guarantys so rationally a 100% guaranty from each of two people (one 740 one 680 for example) is ALWAYS going to be better than just one 100% guaranty from someone at 740 (so it wouldn't make sense to have a better rate for the latter)The problem is that there is fraud and "straw borrowers" out there where someone who is not involved in the property signs on to boost score and terms - so many DSCR Lenders in response either do the "non-rational" thing and price to the lower to avoid the fraud or use the higher of the two (and either be a little loose with things or just stay vigilant on any funny business)

Union City I tend to avoid, there are a few pockets that work for MTR but for the most part the city's rental laws make life very tough for landlords. 

Avoiding Mistakes: What’s the one thing you wish you could go back and tell your beginner self?

Avoid C&J. 

It’s also important to remember that allowing partial payments without a plan can set a bad precedent, so it’s best to handle this firmly but professionally.For the future, collecting the first month’s rent in full before move-in can help avoid situations like this.

You can take it to private massaging if you want to avoid posting about it.

My thought is is use the Rent Ready feature of reporting his payment history to the credit bureau so it can work in his favor as a trade line, but I'm wondering if this is an unnecessary added step since he can already pull transactions on his bank side. 

Plus, Zillow, Rentler and the other real estate platforms tend to have all sorts of unnecessary hoops to jump through for landlords, and I find a lot of their design very un-intuitive (I remember spending waaayyy too much time just trying to figure out simple things in Rentler).  ...why can't they make it easier?

They typically charge 1% of the financed amount but should be able to find a lender to suit your needs and hopefully avoid situations where financing falls through at the last minute.

I’ve found success by focusing on emerging neighborhoods, avoiding flood-prone areas, and exploring short- or mid-term rentals to tap into the steady stream of tourists and business travelers.Good luck!