Dark circles beneath eyes and lines between nose and lips
Botox may help a bit with fine wrinkles beneath the lower eyelids but will not help with dark circles. The lines you describe between nose and lips may be more appropriately improved with a filler.
The cost of BOTOX varies. I feel the fairest way to charge for BOTOX is by the "unit". The The more BOTOX you need to get the result you desire, the more it costs. The most common area injected is the central area between the inner portion of the eyebrows. Injection in this area is...