"Tater Bugs" are fairly common in antique shops and pawn shops in my area, but it's rare to find one in good playable condition. In the usual construction the inside of the bowl was lined with linen cloth, and the bugs seem to like it when they're left in the attic for a few years. Since the bowl is made of many strips glued together, most of the ones I see would need a fair bit of regluing.

In the era when they were most popular (Sears Roebuck sold one for about $5) frets were commonly a fairly soft brass, so you'd want to look carefully at their condition.

If you can find one that's been played, and kept in good condition, they are can be really nice instruments. The big bowl gives them a very mellow sound in the low end, although most lose a bit if you play a lot "up the neck."

They also usually used much lighter strings than are common now, and placement of the bridge "up in the center" on some gave a shorter effective string length on comparably sized instruments. Both of these effects can make some of them very "light" to the touch, and lots of fun to play. Putting modern "bluegrass strength" strings on some of them can be a bit hazardous though.

For a fiddler making a first move to mando, I'd suggest that a standard GDAE mando would be easiest to handle. The larger instruments can be a surprisingly uncomfortable stretch between frets for someone accustomed to fiddle string length. A brief "hands-on" should let any reasonably experienced fiddler know if it will be a problem. Moving from guitar to mando is the opposite, as most guitar players say that mando frets are "too close together."

John