Full refi's or HELOCs?

[Myron McBride]

I own 5 properties.  4 duplexes and my home.  My current plan is to refinance all of them netting around 175K in cash to invest.  I plan to stick with what I know and buy more duplexes or quads.  Assuming duplexes I could probably buy 4 at 25% down and have a little bit of an emergency fund.  After the GREAT REFI, accounting for cap ex and vacancies etc each property should cash flow around $400 a month.  

1) Go ahead and please point out any follies in my assumptions.  2) I'm not sure if just taking out HELOCs on each property would be better than totally refinancing them?  I'm also thinking of rinse repeat the GREAT REFI on all 9 properties in 5 years assuming 3% appreciation and balance pay down.  I am 50 so I can see me doing this each 5 years until I am 65 and then figure out what I want to do with all those properties then.

Good plan?  Thanks