Value of a Heinkel
The magic 8-ball says "unclear". The value of a Heinkel, like all scooters, depends on many factors. Condition, location, rarity all play into the value of a Heinkel scooter.
Heinkels are very rare in the United States. So, you might think the value is higher than a Vespa or Lambretta. This doesn't appear to be the case. Heinkels appeal to a smaller audience. Why? Who knows.
So there you have it. I've provided little help. You might try the classifieds pages to see what others are trying to get for their scooter. Please don't send appraisal email, they won't be answered.