Pay off Mortgage for duplex early or wait out the mortgage period

[Meg K.]

Quick Question: I have a duplex that i have been renting out for the last 2 years. Purchased in 2003 for $90k (more than market value). I lived in one until until 2016 and I refinanced in 2014 to 15 yrs at 3.75% interest rate.  I owe about $56k. Is it advisable to pay it off sooner than the remaining 11 yrs such as by adding an extra $200/mo? or should I keep paying the actual monthly mortgage for 11 more yrs? Since i paid more than market value initially when i purchased it, i feel as if i should pay it off sooner.  The house is located in an area where property values are decreasing.  (i'm not a numbers person so I cannot really figure out the pros and cons from a financial perspective).  Thank you for feedback.

Meg