Is around 800 dollars for 70 units of botox normal pricing?

The cost per unit you quoted is quite reasonable. However, for those areas, I normally inject a total of 25-35 units. The number of units you were given seems high in my opinion.

I do not think that $800 for 70 units of Botox is overpriced, however 70 units seems like more than could possibly be needed to treat the forehead, between the brows and for an eyebrow lift.  Some people do need more than others and if you are getting good results, I would probably just stick with what you've been doing.