Choosing a Scale Length

Along the highest string of a guitar or bouzouki you own, measure from the front of the nut…
…to where the string crosses the saddle. This is the scale length of the instrument. Most guitar scale lengths are between 25″-25 1/2″.
Capo at the first fret. Try playing a tricky melody or widely spaced chord fingerings.
Try the same with the capo at the second fret…
…and at the third fret. When you find your comfort zone, measure from that fret to the saddle along the highest string.