What private health insurance company is the best for the price?? And what is coinsurance??

I rencently got married and it is $300 a month to add a family plan to my husbands health insurance. We are looking for a cheaper way to insure me. We have found a few companies, but what does coinsurance mean? and who knows a reliable, reasonable insurance company??
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~~~Every insurance is different according to your state. Costco has insurance available in 5 states and it's is excellent insurance. If you aren't one of those states I would go through www.einsurance.com They can give you quotes and use reliable companies. Co-insurance is the part of the charge that the patient has to pay. My husband has a $40.00 copay for doctor's visits and also sometimes has to pay some towards his deductible. This would all be considered co-insurance as it comes out of the patients pocket.~~~
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