@dragnucs I also have a small instance (2 users) and have enabled 2 relays. My instance uses around 70% of 2GB RAM and currently 51GB storage. I'm not sure how the storage is split between users/federated stuff or whether I could trim it a bit more though.
@paul seems correct for RAM. However, will need to enable remote (s3 compatible) storage. My server only has 40 GB.
touha.me is one server in the network