5 speed transmission kicks out of 1st gear. on 1996 BMW Z3

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
Happens all the time almost every time I try 1st gear.
(1) Answer
(1) Comments
How much would this cost? I have had same problem beginning at about 65000 miles or 40000 miles ago. Car runs ok but ready to sell and would prefer to have it working satisfactorily prior to sale.