No registration and no invoice for check-out (dont want it)

Hi,

I can see that you already have activated the guest checkout. You can't have the customer skip the checkout. That's the whole point of having a shopping cart system that the customer can add several products in his cart and then go through the checkout, like a real supermarket but online.
Now, there are two ways you can go around that:
- With a payment plugin like PayPal Express Checkout, you can display an "express checkout" button directly in the cart module so that the customer can skip your checkout and only see PayPal's payment page. In that case, the user doesn't even have to enter his email address on your checkout. It will be provided by PayPal when it sends the payment notification to HikaShop and HikaShop creates the order with the information provided by PayPal.
- You include a payment gateway "pay" button (for example in the description of the product) so that the customer goes directly to the payment gateway. It's possible with a PayPal "pay" button. Not sure about other payment gateways.

Besides these, the customer has to go through the checkout.
Now, since you want a different checkout for different products, I would recommend to look into this plugin developed by our partner ObsiDev: www.hikashop.com/marketplace/product/248-multi-checkout.html
It allows you to have several checkout workflows for different products.
That way, you could have a checkout workflow without the "login" and "address" views so that the customer doesn't have to enter any user information for some products, and have a normal checkout workflow with the guest checkout and normal address fields for the other products.