Hello there.
I'm not sure what year you will be getting, but the 89-90 ones that we have access to here in the US all eventually need the rectifier replaced. When it breaks, it will send excessive voltage to the battery and destroy it leaving you stranded. Check the swing arm for battery acid damage as this occurs when the battery boils over and smokes. The one I bought has some acid damage there but still had the old rectifier when I bought it. So all the previous owner did was change the battery and not the rectifier before she sold it to me. So 200 miles later I had the problem.
My fuel pump also went out at the same time. Not sure if it was related.
Those are the only specific things I can think of. As with any used and older bike, check to see if the fork seals leak, tire wear, brake pad wear, signs (scratches) from being tipped over. Look at the oil in the engine at the dip stick. Make sure it's not dark colored or black. Check out the exhaust when its running and look for smoke. Don't buy it if it is smoking.
It's a Honda so if it runs now, it will also run 10,000 miles from now.
Let us know how it goes!
