I'd like to get started this year, but a few questions on what may be the best choice for first RE as a way to bridge to more investments after. 

Bridge financing for 1-30 units would be the best bet.

This was a syndication where we raised $575k and obtained a bridge loan for the purchase and rehab.

You may have already burned that bridge with them by sending out notices to start with, but on the other hand, it might be likely you don't want them anyway and maybe sending the 30 day notice of termination when you did was good (especially if you sent it prior to 10/1).I would have an eviction attorney's contact info in your phone as it sounds like you will more likely than not need it, but personally I wouldn't proceed with the 5-day until the 17th.

I also have some relatives who could loan me additional funds to increase my purchasing power, and I have some investment accounts and 401k's I could borrow against for short term bridge funding.  

I'm curious, though, what you think the bridge is in between 30 and 10.

There is little value in burning bridges or calling banks names because you don't understand their business.

I spoke to gas station owners, locals, NYC transplans.. students and even cops.Took a walk across high bridge in poughkeepsie and wondered, why, with solid employers like IBM , natural beauty and so many educational institutes, Poughkeepsie was overshadowed by Beacon,Also marveled at the beauty of Newburgh. 

For example, if the property is not performing well yet, you might consider a bridge loan.  

Jon is right, the hard money/bridge loan is short term.