I bought an 81 XR100 a couple months ago for my boy, and haven't had any problems other than the points went bad. You shouldn't have to worry about points, the xr200 should have CDI. Bought mine for 300.00, and it looks like new. The asking price isn't bad, but you could probably get it for a...
Any bike is likely to be stolen because they are easy targets. As long as you keep it chained up, or have a lock on the wheels you should be fine with what ever you choose to buy. There are alarms you can get also. If it's an easy target, and some one wants a little joy ride, they will take...