How to price TM using NADA?

[chipper229]

Looking for advice on best way to use NADA to calculate value of 2009 TM 3124KB I'm looking at. It has power hitch, awning, A/C, both hanging cabs and micro drawer, stove cover and propane grill quick connect, LCD TV mount. All else is standard equip. NADA site lists "options", many of which are standard on the TM. Seems to me I should add just options that are true TM options, then add an allowance for the cabs and micro drawer to arrive at a price. Trying to get seller and I somewhere near the same page.... I'm coming up with ~$14,500, and he's north of $18K but quoting many standards as options. I realize that condition counts and that NADA seems to undervalue what TMs are getting in the market, just looking for a starting point. Any advice welcome. Thanks!