how to add product subscription field in woocommerce plugin

I hate to offer an answer that isn’t too much more than a link, but well the question itself is very weak and most importantly there’s little incentive to build this yourself when it already exists as a plugin:

http://www.woothemes.com/products/woocommerce-subscriptions/

You could either create different products for each of the subscription plans, or now it does support variable subscriptions.. so you could just do the different monthly plans as a variation of the same produce.

The only thing I couldn’t vouch for would be the expiration warnings. Otherwise it is a really good plugin…. and you would definitely spend more than $99 hiring someone else to do it or in time to figure it out yourself.

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