Hey Gosha,
1. How much money can I withdraw per transaction to an unverified visa card from e-coin?
2. How much money can I withdraw per transaction to VERIFIED visa card from e-coin?
3. Also, any chance I can use prepaid cards to fund my e-coin account?
the first two were kindly answered for you by @Jeremycoin, and indeed, all those figures are available on both e-coin.io and wirexapp.com
For the 3rd one, there is no direct way to do so, however, you can fund it via bank transfer or alternative payment methods (such as Alipay, Qiwi, etc.) which may allow you to use prepaid cards - but can't really tell, you would need to check directly with those service providers. Hope this helps..