Oh dear, this has all gotten a bit ugly.
I am a qualified foot health practitioner though haven't practised this for many many years. I did my course in the Netherlands and took 3 years and was in combination with a beautician course. Though I didn't start my own business or do it as a line of work in the Netherlands, I do have some wisdom to offer on what has been said.
Though I don't entirely agree with the something 88 person who is a podiatrist, I do agree that 2 weeks of practical work is not enough to confidently treat patients. There are a lot of high-risk patients out there that need treatment for minor things which can potentially turn ugly very quickly if not treated in the right way or treated by someone with little experience. Nevertheless, they do offer these courses and perhaps the government needs to put legislation in place to increase those hours but I don't think arguing about it here is going to achieve anything.
Sterilising is a MUST, not sure who said it wasn't but it is imperative you do. An autoclave is expensive but there are other sterilisers out there and you can buy things second hand often. If you are setting up your own business, you can apply for a loan that can help you buy all the equipment too.
Yes, it can be physically hard but so is any medical profession and with the right materials, you can make things a lot easier for your back. i.e. a good chair that can go up and down for both you and patient. As for inhaling nail dust, we always wore facemasks, gloves and aprons and depending on which drill machine (not sure what you call this in the UK) you can minimise this too as some use spray technique.
To clear up, I was taught to diagnose, treat, advise and refer patients based on what a patient revealed either themselves or what we discovered by eye or gait analysis. We did both static blueprints (? again not sure what you call that here) or walking gait and though we didn't treat this directly we did identify pathologies of the foot and referred accordingly. We also learned how to treat patients with Diabetes and other conditions though not authorised. A further year of studying was required to treat these conditions due to the risks involved.
I set off 2 years ago to do the podiatry degree but decided against it for two reasons. 1) The second-year students were doing everything I had already done and I didn't want to spend 20 grand to do something I already knew how to do. 2) I came across population health and thought it a more flexible career path plus it incorporates everything from healthcare infrastructures to social inequalities. Looking back though, footh health was a very enjoyable profession and very rewarding, different to Podiatry but related nonetheless and very interesting. It taught me A LOT. Often professionals like to slag one another off and claiming its the bees knees over any other profession but it's there to compliment one another.
I've had to go through the biomechanics and podiatry units myself here in the UK. I'm being sent back and forth between departments, it's hilarious but I never fail to capture the rivalry even between these departments. It a tad tedious.
We can be critical without criticising :) My suggestion is look at all the options out there in terms of starting a business and loans, materials, likely income and weigh things over based on that.