Hey James - Just curious is the unit $129 from Troll Music as well? How much to add Frets and go Chromatic - know it is not condoned... But hey if I am paying for it... I have on already but would buy a second to have Chromatic tuning on one.
Any reputed guitar maker or luthier (not one that does just violins though) would be able to add frets, as they sometimes have to replace them on guitars. It has to be done properly otherwise the tuning of certain tones will be negatively impacted almost permanently.