How to monetize the server / Do not go into the red?

Question

Monetization

I got an HP Proliant DL380 G5 server.
36 GB of RAM (4*8GB + 4*1GB)
2x Intel Xeon E-5335 (4 cores * 2GHz)
8 HDD SAS 10k rpm at 146GB, in RAID 5 with a spare hard drive (800 gigs in total available)
I just say I don’t want to sell , sometimes you need it for your own purposes, for study (network administration and setting up a Windows server with a domain controller and all that, I hope you understand)
The essence of the problem is that I live in Germany, the home Internet is IPv6 here, I connected it from a Dual Stack provider, but this is a shared ipv4 ip. That is, I don’t have any ports or a static IP. (For that, the speed is high, ~ 400 Mbps download and ~ 30 Mbps upload)
At first I thought to create virtual machines for example with Windows and give access through a program (analogous to Teamweaver).
But there is a huge possibility that clients, especially from Russia, will be able to carry out illegal activities, such as carding from my IP, etc. etc.
For electricity, I spend 3k rubles per month, if the server is running 24/7 of course.
There is an option to put the server in a friend's server cabinet, there you still need to discuss the price, but if you connect to his Internet, the speed will be only 32 Mbit per second (4 MB / s).
In this case, I will pay only for renting a place in the closet, well, maybe I will agree on 3,500 rubles.
If you connect the Internet there, it will cost extra. 1700 rubles per month (the first two years and then 3200 rubles per month) for 150 Mbps download and 10 Mbps download, for that there will be a static IPv4 IP and open ports.
Prompt options for monetization without open ports and static IP and with it.
What can be implemented, does it make sense to put it in a server cabinet and implement something "serious"?
Sorry for the many letters, I tried to explain the situation in as much detail as possible in order to get the most appropriate answers.

Answer 1

customers, especially from Russia, will be able to carry out illegal activities

It's called Nazism.
Absolutely nothing.

Answer 2

150 Mbps download and 10 Mbps upload

That one shit is different, for the client, on the contrary, it will be 10 / 30mb from the server, he can pull the maximum and, accordingly, his site / server will work at this maximum speed, but the fact that you can download 150 / 400mb to the server is not at all so much needed.
Do nothing, leave everything. He doesn’t ask for food, it’s necessary - they turned it on, it doesn’t need to be turned off.

Answer 3

There is hetzner with servers for 39 euros.
You can't monetize a home server in Germany

Answer 4

it all costs 40-50 euros, however, the channel will be better
easier to sell

Answer 5

I have only one option so far - an ftp server for backups.
Server for undemanding 1s. For several users...
Mail server.
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