1998 BMW 540 Engine Ticking

I,m new to your site, and I'm looking to buy a used 1998 bmw 540i . i drove a car today that I'm interested in buying. 2 problems 1)when the car is idleing i hear a ticking noise. when I rev it up it goes away. the owner said it was normal and im unsure. 2) when i first start the car and put it in reverse while its cold it is solid. After the car warms up there is a couple second hesitation b4 it goes into gear. This car is really cheap and i'm expecting some problems. just wondering what would cause the transmission to do this and wether that ticking noise is normal.