[mediaslinky]

The cheapest lens I ever found was a Ricoh 28mm 2.8 I got for $5.50. I had to cut off the Ricoh flange and remove the pin to make it fit. Took nice pictures, but the lack of coating and lens flare led me to sell it for $10.

Pentax M 50mm F2 for $20
Vivitar Kiron made 75-150mm f3.5 for $20 (sold it for $30 later)
Vivitar Kiron made 75-205mm f3.5 for $30

I just bought another Vivitar, Kiron made 28mm... if it has the right mount, it will be my best buy- $15.75. if it has the wrong mount, it will go back on ebay. I like Kiron lenses.

I got an off brand 2x tele just to play wth attached to another M 50mmf2, and turned around selling the m50mm... net cost was about $5.