Hello there, DO got a really great system with registering new accounts and sometimes thats why things need to be verified or they need more information.
1) This is all because DO wants to be sure nothing goes on on their systems they don't want. Don't make a big deal about it.
2) Each Droplet is billed per hour up to its monthly cap. You can choose to fund your account via PayPal or you can pay your monthly bill via credit card.
How do you choose between monthly and hourly billing?
Each Droplet is billed per hour up to its monthly cap. The monthly cost of your Droplet is calculated by running the hourly rate for 28 days (672 hours). Once you reach that amount (e.g. $10/mo for a 1GB VPS), you will not be charged for your server's additional runtime. This allows you to destroy your server before the maximum monthly charge and pay only for what you use.
3) The verification process is automatic and happens usually within 30 days of opening and using your account. After you become a verified user, you will be able to manually charge your credit card by using the “Pay now” button on your billing page and we will periodically increase your Droplet limit.
If you got any more questions don't hesistate to ask them.