on the old air-cooled bikes, replacing a cam chain is *dead easy* - all you do is lift the cam-cover off, get all the slack in the top of the cam-chain run, split the old chain, then link one end of the new chain onto the old one. Take all the spark plugs out.
You need a mate to turn the motor over with a socket on the end of the crank, keep the tension on the chain, and slowly wind the motor over, while keeping tension on the front run.
Your other hand will be busy slowly pulling the cam chain on the back run, keeping it fully tensioned. Once you have pulled through all of the old chain, you simply link the ends of the new chain together, and peen over the end of the chain once the side-plate is fitted.
I have done this on heaps of Zeds, but it helps if you have had practice. On a water-cooled bike I would expect the job to be much the same, but you would need to replace any O-rings or gaskets as well as the cam-cover gasket.
Doing it this way means the head does not have to come off. It saves a heap of money and time - BUT you have to be *really* careful, keep the tension (and the cam wheels) moving correctly, otherwise you might get the cam timing out.....
If you are not comfortable with this technique, it would pay to have a bike mechanic do the job. According to my Z1000 workshop manual, I am supposed to remove the crank to replace the cam chain !!!!!

Not fuckin' likely at $80 per hour...