If you are concerned about the memory issue then you should pitch the server and buy new. The cost of upgrading is probably not worth the expense. Adding a new hard drive and/or memory is trivial if you can do this work but if you need an IT person to do it the cost would be the same as purchasing a new computer.
How much memory do you have in the server? Are you referring to RAM or hard drive space? Is the current server "slow" and not working optimally now?
You can migrate the server software to a new computer if needed.
It would be helpful to know exactly what the actual OS is on the server.
