Firstly Dropshipping is a lot of work. Be prepared to handle the customer inquiries. If you are not ready for the additional workload then this is not for you.
Second, payment processor. Most if not all payment processor DO NOT LIKE DROPSHIPPING. In fact even paypal frown upon dropshipping due to higher chargeback rate. Eventually you will be asked for invoices from suppliers (as paypal assume that you place the order and paid in advance) and if you explain that you are a dropshipper,they will most likely limit the account and say thank you for your business but due to risk management they decide that they cannot continue the business with you.
Payment processor can be a pain. Sort this out before you get into dropshipping.
Third marketing, you have to make sure that you are selling something really unique to standout from the crowd. People do not just come to your web shop and buy. Where is the trust? Why should they trust to buy from you?
Product sourcing is another area of problem. How do you handle the unreliable shipping timing from China supplier? How do you handle the situation when product get stuck at custom for taxation? Who is going to pay for the additional taxes?
Look through your list above and if you can answer all then you are ready for the basic of dropshipping.