Need some advice to increase my storage capacity

I have an old computer that I use for storing and streaming my media. It has an attached external drive. I would like to increase my storage and build something that could be extensible to at least 100TB. I am not worried about backup.

I looked and I think I need a HDD rack or enclosure. Some people gave me links to good deals on ebay and some other sellers but they are based on the US and shipping fees are high. I saw this HDD enclosure and it seems to be what I am searching but I don't if they are good.

Do you have some advices for me?