Turbulent Market for My Rental Properties

Last night I received news that my tenants at my newest and largest house will be breaking there lease early due to job relocation of both tenants. This comes just two months after filling my smallest of three rental properties, which didn't draw rent since January 2008 and required $15k in rehab work. I recently started making payments of $2300 over mortgage on my smallest rental property. This accelerated payment plan would have allowed for paying off the smallest property in only 5 years. Unfortunately, this will be placed on the back burner until my largest house is under a new contract.

My wife and I have three rental properties (3100 sq ft, 1900 sq ft and 1450 sq ft houses). We're in no hurry to sell them, but are nonetheless entertaining both sale and rental contracts each time our rental properties are empty. Our focus going forward is to pay off each of our rental properties ($296k balance due) and pay off our retirement home before I retire from the military. This goal isn't that lofty since it's likely we'll retire in the south east where properties are more reasonably priced.