The United States is the most popular location for RDP servers due to excellent connectivity and content availability. However, pricing can vary significantly depending on the provider and the state.
Generally, servers in Dallas, Texas and New York/New Jersey are cheaper due to massive competition and low power costs in these data center hubs. Locations like Los Angeles or Silicon Valley tend to be slightly pricier due to higher real estate and power costs.
Be aware of "Windows License Fees." Some providers advertise a low price (e.g., $5) but add a $10 Windows license fee at checkout. Always check the final cart price.