Had another guy whose wife left him and took his vehicle and credit card. 

My credit score is 690 and her's is 684.

2) Is it possible to apply for a mortgage without anyone's personal credit? 

I would let them know that an eviction is not just another collection item on their credit and it will be a very large red flag for future landlords and other credit grantors.  

You would use their money to purchase, and do the repairs as quickly as you reasonbly can, then go to your bank and get permanent financing (or get your whole mortgage as a HELOC if you can find a bank/credit union to give it to you that way).It'll cost you a few points to the hard money lender, and a 10-12% rate for the time you have it. 

LOTS of people get down payment gifts from family, and LOTS of lenders & borrowers prefer that gift funds go directly to escrow to keep the paperwork a little lighter (one less round of "source this deposit" and bank statements and transaction histories).

Has anyone used an unsecured line of credit to make their first investment? 

We have thought about getting a line of credit through the bank, pulling in another partner to help out with cash, and also private money lenders. 

It's been a long time, so my memory is a little fuzzy, but it seems like we may have also offered a credit on their next month's rent to offset the higher cost of utilities during that time as well.

So my question I have is would it be possible for me to get a LOC (line of credit) with my local bank and then use it for down payments on my properties I want to invest in?