I would have thought that it was not economically nor practically viable.
Practically you need people in the local vicinity to make use of it. So how many people in say a 20 mile radius are going to be interested? Realistically people with a few animals are most likely to be lacking in much of the equipment they would like to have. They are also those less able to justify, or afford the costs of hiring. They are also least likely to have the means to transport the system. For you to transport it to them, in terms of your time and fuel would be uneconomic.
Larger farmers are more likely to have a suitable system already sorted. Ok - not all of them will have - but do you think those that haven't will be prepared to pay someone else for the use of something that they don't consider sufficiently important to sort out for themselves?
Do yourself a business plan.
Work out for yourself how much a system is likely to cost.
What sort of return would you expect on it/year?
So how many times a year would you need to hire it out, and what rate do you think would be acceptable? By that, I mean - not only to you but also to the people that you are targeting.
Under what circumstances would you consider people would feel it beneficial to use your system as opposed to the method they were already using? (Bear in mind all cattle keepers need to have some form of handling system in place themselves for TB testing and emergencies.)
I myself run 40 cattle on mainly rented land. This means that every time I change fields, the cattle have to be gathered up and transported by road. We achieve this with the use of 9 heavy duty, 5ft high, cattle handling gates which cost us new £86 each, and an old Ivor Williams flat trailer which cost £250. Total cost @£1,000. We use it at least 6 times a year and it's always available in case of emergency.
Would I ever have considered hiring before we got this system? No. Before that we used a series of field gates tied together with rope to handle the cattle. It worked but was nowhere near as safe or reliable, as they could and did jump out at times. But rather than hire something better we saved our money till we could afford to buy a better system of our own.