Suitable amount of RAM needed to Host TTT on VPS servers

I’m just wondering, if 512Mb of RAM on VPS Linux Server hosting is enough to host a TTT server?

Yea this is more then adequate. But depends you haven’t said what OS your using 1gb would be better.

enough for 24slots of players? :o

No. The Linux OS already uses roughly 100-200 MB of RAM. Since Source hardly ever uses more than 700 MB RAM, you should aim for 1 GB. 2 GB won’t hurt, but 1 GB would be the bare minimum if you ask me.