How much it cost to build 4G proxies system? using Raspberry Pi & dongles

Hello guys, I want to start building my own 4G proxies system, and I have a question for those that built one successfully:
How much it cost you for the whole system? I need 1 Raspberry Pi, USB hubs, and 10 modems max, How much should these costs?

Looking forward for your replies.

Cheers!

I have the same question. Did you ever figure something out?

I've setup multiple systems for a couple of clients so far. I didn't really handle the costs for the hardware, but I got paid a minimum of €1000 to setup the proxy system that automatically refreshed ip of the sim cards every xx seconds. If you can do it yourself, you'll only have to spend money on the hardware.