help with ''linkage cable''
 

hello
im trying to get some help with a 99 porsche boxter, this right now is for sale by my neighbor and i would like to buy it but he says that the ''linkage cable'' needs to be replaced, the shifter feels very loose and it only shifts to 3rd and 4th gear, i wanna know if there is something i can fix my self and how much would it cost me, if i need a special tool. ive never have a porche before so im new with these cars. thanks!