Living rooms take a beating, but refinishing the wood changes the entire feel of your home. The process usually takes three to five days, though you will need to plan for a few days of downtime while the finish cures.
Aim to book this during low humidity months like winter or early spring. Wood expands in summer, which can make the sanding and staining process trickier for your contractor.
Remember that this is a temporary window, not a free pass. If you have a remaining balance after the 18 months are up, you will start paying interest on whatever is left over.