Originally Posted by matt h
If you havent bought it yet. Why dont you buy an electric start model?
Presumably he is not seeing packages around like that (in budget).
To answer the question, it will be expensive, some will be easier than others but I think as well as the starter and all the wiring you will need new fly wheel, and alternator, regulator, etc. even doing it yourself, with second hand parts don't expect much change from 500... and several hours work for someone who knows what they are doing.
Now, why does he want electric start?