The original question is tough to decipher but it seems like you want to take out a $400 30 year fixed loan and a 2nd on the home for $150 totaling around $550 instead of just doing a 30 year fixed mortgage for $550. This way you can have a lower monthly payment by having a P&I payment for $400 and just an interest only payment on the $150. In another couple years you are planning on paying off the variable rate loan and having a fixed 30 year at today’s rates instead of refinancing. If that’s the case I think it makes sense.
