Thats about the right price. Make sure it has the 3 heads with it.
How long each head lasts will depend largely on you. Dark juices tend to deposit more "crud" on the head and the head will cleaning more often. cleaning the head will ensure it lasts the longest life possible.
I vape a lot of dark juices and get about 3 weeks use out of one head - I clean about every 3
tank fulls or so. Mind you this is just my personal experience.
You can get a much longer life out of your heads by simply rinsing them off under warm water every other tank. For more through cleaning try soaking the head in alcohol or my personal favorite, denture cleaner, for a few hours. Rinse and let it dry.
The tank its self will last indefinately and your only real cost after initial purchase is to replace the head. they cost 3.00.
For me this is a perfect price point. I dont have to replace very often and its cheap to do when I do need to replace the head. You can lower your cost further by learning to rewick the head yourself. This I cannot offer any opinion on. I feel that 3.00 is pretty cheap already!
Other clearos cost less but many of them are not rebuildable and thus - you just throw it out and buy another when it no longer works. per use cost goes up dramatically.
Dont buy for "cheap right now" - buy for what will give you the best value in the long run.