I'm running multiple masternodes on one vps - whether you can run multiple nodes from the same chain depends on the code. Some coins lock the ip address for mainnet, others dont. If the port is locked, you can only run one node for that coin per ip address. So the options are:

1. Run multiple coins - each has a different port, so they can all use the same ip address
2. Run coins that allow different ports - same ip address
3. Order more ip addresses
4. Use ipv6 if it is supported by your coin

I use a different user for each coin - that way the default installation works without having to pass additional parameters when running the commands.