Advice for refinancing 5 properties purchased my first year

Hi, I am brand new to the forum and from what I have read so far it seems like a wonderful resource for real estate investors. 

I recently graduated from college (May 2014) and quickly started investing in multi-families.  I had some cash of my own and I quickly got up to 29 units.  I was discouraged that traditional banks required 2 years of taxes so I obtained financing from private lenders.  My current loan amount is 565,000 from a private lender for 16 units that brings in 16,000 a month (Two 4 families, one 3 family and one 5 family). I am nervous that despite a good credit score, a good job that pays 120k a year, and tremendous cash flowing properties, that I will encounter resistance from banks.   I have renovated every unit and increased the rent roll 25% on average in all of my units.  Am I better off trying to refinance a few of the properties at once (after 6 months) at the higher appraised value because I purchased them below market value or should I do one property at a time and shop around with different banks.