I pay 16% management fee, but that includes all maintenance calls, snow removal, lawn care, rent collection, evictions, inspections, rental-ready, picking up trash, cleaning.

It's great that you're taking care of your parents.  

They didnt really care because the house was the collateral. they never asked for a down payment unless a so do deal.

Both units also need brand new septic systems, which the seller will replace.My question is...should I wait the few months for the seller to take care of all of these issues and make sure that it is done right before I purchase, or should I offer him a low-ball cash offer to walk away and then get a HELOC on the property to purchase my next investment.

Lastly, since everybody has different investing goals I'll leave you with this: Even if my return is zero or even somewhat negative during the repayment period, in 15 years (actually quite less on many of my properties now) once the properties are paid for and still generating a ton of cash is when I will enjoy the returns...I can see it now, I am 60 years old traveling the world with my wife and not a financial care in the world, and when I am 80, my kids  saying "Dad, your so cool, we're really glad you bought those houses"Cheers, Lawrence

but first,  seek for mentors who are not promoting their mentor ship program, who are trying to make money and may not care about your well-being.

Any lessons learned from your first out-of-state multifamily purchase that you'd care to share? 

When necessary, I will need someone to take care of tenant move-outs and finding new tenants, as well as evictions.

If you're one of the  lucky ones that finds a buyer immediately who is qualified, agrees to your price, doesn't care if you've missed a disclosure, isn't picky at the inspections, and basically just wants you out and them in, then you don't need an agent. 

I got started in the Private Equity sector and REITS, every time I see a post with the term Multifamily in it, I immediately think multifamily over 100 units, however on BP not knowing the exact number I'd probably guess 97% of the post titled multifamily are actually post about Duplexes, Tri-plexes, and Quads, which are terms the Guru's have steered away from since using the term multifamily will get you more attention.