Lamotrigine costs me $1.97/month for 30 tabs of 150mg. It's my cheapest prescription. If I didn't have insurance coverage, it would still cost me under $20. It might be worth "shopping around" for other options. I don't know what the rules are on prescription pricing, though.

Starter kits are brand name and super-expensive. You should be able to get the necessary small increment doses in separate prescriptions at much lower cost - it's just more nuisance for the doc to write up and for you to keep straight. It did not cost me anything near as much as that for me to get started.