1. Both and then some. Why limit yourself?
Your website should be fairly static. The only time I update my website is when i want to add knife pictures to the gallery. If you plan on posting your completed non-sold knives there, then keep that updated. BUT, if you do start a website, update it and make sure it is good looking. Nothing is worse than a broken link or under construction page. But you are IT, so you know this.
Post often to your Facebook page. Doesn't have to be everyday, but often. Join knifemaking groups on Facebook, and share your stuff there. Lots of non-makers join those groups.
Start an Instagram account, and post there all of the time. Tag the living hell out of your pictures. Comment on other knifemaker's pictures. I have gotten more commissions from IG far and above any other mechanism. It is a pretty international platform too.
Social media sells knives. Be your best promoter.
2. I use PayPal, and have never had a problem. But, I have no idea how hard it is to remediate a problem with them, since I have never had one. I have heard its gotten a lot better over the years. Here, check out this article for alternatives.
Also, I know you are hundreds of miles away (if not more) from South Africa but they have a pretty healthy dose of excellent knife makers there. Check out Black Dragon Forge, who is an ABS Journeyman smith. He teaches classes all of the time. If you can't make it to his shop, maybe he can give you some advice for the upcoming knifemaker in your region of the world. Also check out Wayne Morgan, who happens to be one of my favorite makers. He is from SA as well. Talk to those guys and see what they have to say. Both of them sell internationally all of the time, and they could give you some great feedback I'm sure.