Sell videos using pay per view

1. Have word press site
2. Selling videos . Using PPV set up because it has timer so I can control the amount of time a user can view the video.
3. In order for timer to work, user has to Log in. They have to click "view my video" . Then a drop down happens where they get choice to log in with 3 options FB, Google, Word press.
1. Ideally, I'd like user to be able to create username and password. (as I personally don't like using the other two log in choices) Is there a way to do that? 2. I'm confused about use of word press sign in. If I saw that I wouldn't even know if I should use it. That said, when user logs in with word press if they have previous wordpress sign in, and go to create new, not realizing whether they have one or not, does that present a problem? Will it not work for them? [ For instance, personally I have a word press sign in which is my sign in to the site, but if I were on someone else's site and paying to view videos I'm not sure Id' put two and two together-- maybe others are not as tech-dense as I? My concern is peeps will go away if takes too long. AND they must log in FIRST before they PAY. So if they go away, they don't pay. LOL. So to recap: is there a way to create a simple user name password log in and not have be word press AND still have the timer work to control user's viewing time on video? Or is there another way to do all this?