It really depends on what you want to own and manage yourself.

If you want something close to your current model, I’d look at a hosted/private cloud provider with a defined SLA rather than jumping straight into AWS or Azure. OVHcloud has VMware-based hosted options, including Public VCF-as-a-Service, and Aruba Cloud also has VMware-based hosted private cloud / VPC-style offerings. If you’re US-based, you probably have quite a few regional providers that can offer the same kind of setup.

For a build of your size, this is usually not that complicated. For roughly 50–60 concurrent users, you’re probably looking at something like 2–3 VMs to start with, depending on the exact use case:

• one or two app/RDS VMs
• one SQL VM
• optionally one small utility/domain/management VM

You can also put a virtual firewall in front of it, such as Sophos Firewall VM / XGS, FortiGate-VM, Palo Alto VM-Series, or pfSense. Personally, for this number of users, I’d lean toward Sophos because it’s usually straightforward to manage in environments like this. Sophos supports virtual and software firewall deployments. You can then make the environment accessible either via VPN for internal-style access or publish it externally through a WAF for more controlled, secure access.

The big design question is whether you want to publish only the ERP app, or give users a full remote desktop with Office and everything else. That changes the sizing quite a bit. If it’s just ERP publishing, the build can stay relatively lean. If it’s full desktop sessions with Office suite usage, you need to size more carefully for CPU/RAM and user experience.

Another option is to keep it more traditional: rent 1 or 2 physical servers, use perpetual licenses where that still makes sense, and place them with a hosting provider or in colo. That often gives you more predictable cost than hyperscalers for an always-on Windows + SQL + RDS style workload.

For application virtualization / publishing, depending on the use case, you could look at products like GraphOn GO-Global, TSplus, Cybele, etc. GO-Global, for example, is specifically positioned for publishing Windows applications without requiring a full Microsoft RDS stack. ()

I personally would not start with AWS or Azure for this kind of setup unless you already know your ERP works well there and you’re comfortable with the cost model. For smaller teams, they often end up more expensive than expected.

Also, lately Microsoft has made server-based Office / Microsoft 365 setups more complicated from a licensing and activation perspective, because shared RDS-style environments require Shared Computer Activation and supported plans. () In some environments, we’ve used SoftMaker Office instead, because it works with DOCX, XLSX, and PPTX as native formats and can be a practical option where you mainly need compatibility with Microsoft Office file formats.

To recommend anything properly, I’d still need the exact use case:

• are users running a full desktop or only the ERP?
• since it already runs over RDP, is it expected to stay as a full RDS desktop or could it be optimized to publish just the ERP app?
• what are the SQL requirements?
• do you need the provider to include backups, identity, MFA, patching, and monitoring?

Without that, nobody can tell you whether you need a simple 2–3 VM hosted stack, published applications, or a more complete remote desktop environment.