Hi - I can help you a lot, in fact that is one of my (voluntary) roles within a domestic cleaning trade association - advising new cleaning business' to start-up and make progress in a professional way.
This is a huge topic and if you would like to pm me I can help you with any question and will do so with pleasure, I am all for raising standards within the insudtry and will advise accordingly.
You will definitely need to be insured for public liability and registered as a business even if you are a solo, self-employed trader.
As per client expectations, I could write a huge post but basically you need to provide a 'staple' standard service which includes cleaning the kitchen, the bathrooms, dusting and polishing, vacuuming the rooms, mopping the hard floors (after vacuuming them of course).
Then you need to decide which details to include within your standard service and which to supply as 'additional services' for an extra price.
These can be interior windows cleaned, paintwork wiped/washed down (skirting boards doors etc), emptying the bins, inside microwaves etc.
Basically it is YOUR business so you include whatever you want to, demand is so high for services that once you are established and delivering a quality service you will be able to pick and choose your clients, you never need do anything you don't wish to include, but anything you do include will be a selling point to focus on when you provide quotes to potential customers.
You must decide if your business model is to be 'per hour' or a flat rate 'per house', the latter is our business model but takes some experience to sell effectively and not end up out of pocket, I like 'per job' rates because it is more flexible and allows for different staff members performing at different speeds however 'per hour' can be good while you get the hang of pricing.
You need to decide if you are supplying the chemicals, materials and equipment to perform your service or rely on your clients to supply these, pros and cons either way.
Important tip! - If you are intending to grow with staff at any point do not set your price too low, £10 per hour is far too low for this, it will end up your 'break even price' if you are lucky, you will need a fair amount more, luckily there are many clients willing to pay a LOT more for great service but you will need to get established first.