The 5th gen are the easiest to sell. 2 weeks ago there was a well farkled 1999 on CL for $3500 that I tried to buy.
$4k is at the higher end of the market without the hard bags and ABS. $3.5k that you mentioned is not a bad price. Understand that most used VFR buyers get steered towards the 5th gen. A 6th gen with ABS or hard bags will tip the scales in favor of the 6th gen.
$5k is too high for any VFR(750 or 800) unless it' a 2005+ 6th gen with ABS, Hard bags, some nice upgrades and in mint shape.