What can I use to expand the memory of an XBox Series S?

I bought the new Xbox Series S and after 6 downloaded games I already ran out of memory. Now the question arises whether you can expand the storage with an SSD (except the official one from XBox + Seagate, since this costs 240 euro for 1 TB) and how much would that cost? Ideally one where you don't have to sacrifice performance.

No is not possible. If I were you, I would have got either the PS5 all digital or the Series X. The Series S is quite a piece of junk in terms of hardware, which we won't have fun with in the long run. The GPU of the 100 euro more expensive PS5 is better by a factor of 2.2 … Not to mention the memory.

You can connect a hard drive via USB 3.0.