Hi M G,
I can give you two options:
1. You can use Citrix (but I think it's expensive) .
2. You need to setup a Terminal Server (so your client will use Remote Desktop Connection). In our infrastructure, we subscribed from our Internet provider IP-VPN it has an added cost but not as expensive as Citrix. (You can ask your provider for this feature).
Wr,
Paul Caballero