I think to run 10 MT4 you need at least 4 GB RAM VPS as per MT4 can includes 2 or 3 chart. Recetnly I took VPS from https://www.fxsvps.com/
premium plan and its working really awesome. I added around 10 MT4 with multi chart and running trade copier as well and RAM and CPU uses very low.
VPS price also very very reasonable comparing 99% Forex VPS website.
Trading Psychology is very important for trading success!