Getting your user agreement right

Question

I'm planning to provide a little service with which you can control your computer from anywere. It exists out of a server (which I will be providing), and two clients (a controlled one and a controlling one). Now I want to provide that service for a little fee. However, the server is actually a small old Dell laptop with a broken screen at my home with Ubuntu as OS. It's not very reliable, but I want to use it, because it's cheep.

Now, as I said already, the laptop maybe isn't the most reliable machine, along with my Internet connection, which also can go down if there are some unexpected problems. But I don't want to take risks, and let the user, before he pays, know that this can occur. But I also want me to be safe, so I won't need to give any money back.

It is my first application that I will be giving away for a little fee, and I don't know about the legal responsibility I have to take. Basically I don't want to give any money back, even at a 100% downtime (which will be very unlikely), but I also don't want it to be my fault if someone loses data, by using my software, even if it is a bug, or someone intercepted his data.

So, I have put this in the agreement, and this only. Is it enough and is it legally binding?

What should I also know?

• iControl actually implements a client-server-client protocol, where one client let's the other client execute a shell command. Then the controlled client will return the termination status, the standard output, and the standard error of that command.
• iControl uses no encryption to send data over the network. It is a potential security risk to use this service, because all data is sent raw over the network. You can compare it with the FTP protocol, the HTTP protocol, which you're using right now, and the telnet protocol.
• iControl's maker does not in any way stand in for the damage this service can do. Not by misuse by the user, not by a bug in the software. No illegal activities maybe done using this service. The provider of this service may suspend you from his service at any time without an explanation, without a money-back guaranty. The collector of the rent fees does not need, in any circumstances, to return the payed money.
• The iControl service is maintained by one man and one man only. Any downtime of the used server may occur. In case of any length of downtime, the service provider does not have to give any money back, however he'll do his best to make you as happy as possible by trying to make the service be up all of the time.

I'm planning to let the user check a box that they read this and agreed to it, when they register. Is this enough?