Shameless self promotion 2 - My first ever banjo sale to colleague from work for £25 (below) Made from a tambourine, cut out plywood ring to hold the tacks and one of those 'woven' serving trays for the back not visible. The nut is made from two dowels and a bolt glued together and the tailpiece is made from the end of a pair of serving tongs.
It also has a piezo pickup disc from a door alarm ( dirt cheap from Rejects) soldered to a 3,5mm input jack so it can be amped if needed .The skin is again a shrunk P.E.T.E. 2 litre Aldi lemonade bottle . The design is based on one by Frank Proffitt style banjo (bottom) except that one is an open back and has an animal skin I believe.
The customer was delighted at the purchase even being a six string guitar player and surprised at it's playing simplicity - 2 strings at same gauge tuned to the same pitch, slide and plectrum. I played a couple of tunes for a few folk including the gaffer until my nerves got the better of me - and I had to start work...Not out to make a killing on this- I asked the customer to haggle for the price - just got the bug of making/improving and playing and enabling others to do the same.