I use Quickbooks online for the formal accounting so it's easy for my tax guy to get in there and do his piece every year, since I have an LLC per building.

ONLINE PRIVATE LISTINGSIf homeowners are looking to sell without a real estate agent, they’re likely on social media.

Anyway, I'm thinking maybe HF has more advantage for online bidding, as they could essentially create many virtual IDs and have a large pool of fund to leverage.

I would recommend first, finding and joining at least one if not more local real estate investor (REIA) meetup groups (look on Facebook or Meetup or just search online) and try to attend as many as you can to network with local folks doing all different avenues of investing.

Since you mentioned investing out of state, I'm assuming you're asking about getting a partner online, or at least not a friend/acquaintance.

Do you believe online accounting services like 1800 Accountant are good for the owner of a Real Estate LLC?

People will hear podcasts online about how a 25 year old investor bought 65 billion properties in one week and think that they have to do the same thing. 

We have worked on improving the physical appearance and infrastructure of the park, updating the homes, getting a new sign, advertising it online, and creating a website (www.shadyacreshuntington.com).

Should I be visiting, asking neighbors questions, getting a feel for the neighborhood and home (in person rather than just off of online research) before buying or making offers? 

A friend of mine attended one and found it incredibly helpful..they even walked through actual deals they've closed in the area.Don't overlook online resources either.