We have a 20 year old 4 plex, we bought 5 years ago by assuming a non - qualifying assumeable loan at 9.5% with 17 years left to go. ( Yea, we bought it wrong) Today’s value is about $165,000.00. We owe about $128,000.00, PI is $1,245.00. The lender (GMAC) is offering a refinance to a conventional loan at 7.75% - 15 year note. New balance would be $132,800.00 and the new PI would be $986.00 and rolled in the closing cost ($4,800.00) in to the loan. ( or keeping the non - qualifying assumeable of course add those cost too)
If you use the same rule of thumb that the costs of refi need to be saved in the next two years then you would do it. However, you say you have a loan that will pay off in 12 more years. The new loan would be 30 years but reamortized. Some of the savings is just reamortizing over a longer period. The rest is interest reduction. If you can discipline yourself to pay or invest the saved amount then financially it can be worth it. If you plan on reselling anytime in the forseeable future the existing loan make it very much more valuable as far as liquidity.