Although I'm not investing in the 2 markets you mention, we do have several properties that range from the coast of NC to the Mountains of NC to California and we self manage all of them so have experience with long distance STRs. 

Lots of potential sources: other investors, family / friends, personal loans (I've used SoFi & Discover in the past, they loan in the $35-50k range depending on your credit), 401k loan, margin account against stocks you own...Just make sure to factor in those payments in the overall numbers.

Total access to funds: $160kPreferred type of investing: Flipping single families and/or buy and hold multi-families I would like to pick up more properties (especially apartments in the 4-12 unit range), but given the fact that most money is investor money, would need to know how to consistently get the money back out to them. 

30 year investment rates are closer to the 4% range, and I would imagine private money is going to be more than 4.5%.Main benefit of private money is to avoid jumping through the hoops and red tape conventional financing can bring.

Also, I would like to know generally for contracts, legal advise etc. can i use a lawyer nation wide?

Lots of people are OK with that because a lot of times people buying in that 2 to 5 million dollar range are more "sophisticated" than someone buying their first home or investment property and they know their way around the deal and don't need guidance, they just want to get the deal.If you feel comfortable with the deal process and economics then I wouldnt worry about what the listing agent is going to earn but if you are worried about getting hosed, you probably should be and hire an agent to work on your behalf.

Cap rates range from 6-9 in these areas. 

I reached out to the owner of a local park and they expressed interest in us purchasing one or more homes in their park, and assisting us with renovating and renting them. 

I think that I can afford a smaller home (1,200 sq.ft or less), but it would be towards the upper range of my budget (approximately $600K).

Credit scores are highly over-rated IMO as long as they are in a decent range.