What type of lending is best for me? commercial, res, portfolio

[Jake Riner]

A little about my situation -  

I owned a business in my town for several years before starting the REI thing. During that time i built a very good relationship with the current bank i am using and, more importantly, built a good relationship with the commercial lender in the bank. The bank is a large national bank. When i bought my first rental it was a duplex and i started an Inc. and bought the property using the commercial lender under the corps name. Partly because i trust them and they have given me a TON of advise and definitely gone above and beyond.

I currently have 3 loans with them. 2 are 10 year loans with a 5 year ARM between 5-6% and they usually require 20% down although i did buy one on a HELOC and just paid it off when i sold the flip.

The other loan is an interest only loan they gave me to do a flip that i have finished but wound up renting immediately after i finished (complicated and a story for another day).  Regardless i would LOVE to keep this house as a rental long term and i have about 100K equity in it currently.  

SO I FINALLY GET TO MY QUESTION!!  

Is the commercial lending really the best option for me???  I have already talked to the bank and if i do refinance this "flip" and keep it long term ON THE RES side then i could get a fixed 30 year for under 4%.  I could also get 80% of the appraisal cash out if i wanted to finance my next deal.  I think it will appraise for 225k or more.  

I have considered shopping around for a portfolio lender but i REALLY like the people i'm working with at this bank. They have show a huge interest in what i'm doing and the lenders even stop by properties i am rehabbing. They have given me a LOC several times.

Is it any safer to use the commercial side? It seems like they care a lot less about my debt to income and look a lot more and my asset to liability. In other words down the road it may be easier to acquire more properties on the commercial side vs the res side??? I am also probably going to own a commercial property at some point so thats another benefit to using them. With interest rates so good at the moment i'm just not so sure a 5 year ARM on a 30 year loan is what i want to do. Especially when the interest rates on the commercial side aren't as good in the first place.

Should i refinance all my properties to take advantage of fixed and lower rates on the RES side??  I could keep the two i have where they are at since i have like 8 years left with with 5 year arms ??  Should i just do this one since its a bigger property and i want to do a longer loan on the RES side to take advantage of the fixed 30?? 

Really appreciate you if you made it all the way though this post :)  any and all advise would be very appreciated!!