Hi and welcome.
I think your friend has a problem. If he didn`t think it is importand to have a website until now, don`t have him spend a lot of money and time for a online shop. We are selling rugs online since 12 years on ebay and our own online shop. At the beginning it was just a little game and a lot of fun, but now it became a real piece of hard work. If you are planing to open an online shop, you need to be able to do a lot of work with the computer like uploading, updating, anwsering a lot of emails every day (most of the time for nothing) and so on. Your friend seems to have the time - so this is ok. But if he is not able to do the mentioned work, he will need to have someone do this for him. If you have this done by a pro, it will cost him a lot of money and there is no guarantee anyone will buy anything from him.
Also customers in Germany still prefer personal contact. We do most of our online shop sales internationally to Canada, UK, France, Italy and South American countries. If you think "I will open an online shop and everything will be ok" - forget it! Most big players in the market have their rugs online by now, and if you want to compete with them you must have competetive prices and competetive cost structure handling the online market.
Best would be to start with a well made website without online shop. Check the trafic and then decide if it makes sence to spend money for the online shop.