Ordering with other VPN

VPN
1

Am I allowed to order with Swiss VPN to Austria?
It is 50€ cheaper on BambuLab

2

So the order is: 420+28€ Shipping and in Austria it is 510+10€ shipping do I need to pay import too?

3

If I enter Switzerland, and then I go to Express Checkout with PayPal it says deliver to my Address and it only charges 440€, do I need to pay customs when it arrives in Austria?