We are in the South East. All depends on facilities, type of yard etc. but at a good clean, successful yard, with secure tack room, wash facilities, school etc these are the minimum prices needed to make any money out of it, and even then, if just DIY, it's hard to make a profit:
DIY - stable and grazing only (no hay or bedding included) £200pm. Adding in ad lib hay and bedding would bring it up to £300pm or £10 per day.
Assisted DIY - varies depending on services. DIY rate plus time at £20ph. Don't under-estimate the time used for these services
Part - Everything included except riding (includes full care such as grooming, holding for vets, farriers etc.) I charge the DIY rate of £200 plus £20 per day for services of the groom, plus hay at least £50 per month plus hard feed depending on requirements so my starting price would be £900pm (£30 per day).
Full - Includes riding/training etc. Starts at £1200pm (£40 per day) but depends on requirements, as that would include the horse being ridden or lunged/long-reined 5 days a week.
The DIY rate only really works if you have a large acreage so the horses have all year turnout and large fields that can be rotated and harrowed rather than poo-picked. Be aware that expecting all DIY liveries to poo-pick daily, even in appalling weather, is unrealistic and so the land always becomes degraded and horse-sick over time.
The hourly rate of £20ph may sound high, but once you factor in the costs of employing someone, including paying for their holidays, training, sickness, pension, NI etc. this is the bare minimum it costs the employer to provide a basic full-time employed groom for an hour. If you are doing the work yourself then maybe you could reduce it to £15ph but why would you work for that!
On part or full livery, as a client I want to be sure my horse is well looked after so anything less than an hour's time each day is skimping, when allowing for feeding, mucking out, hay and water, turn out, bring in, rug changes, evening checks and skip out, grooming, picking feet, clipping, tack cleaning, holding for vets, farriers, physios, etc. I challenge anyone to do all that properly in less than an average of an hour a day or 30 hours a month!
The Full livery price assumes the horse is backed and can be handled and ridden by any reasonably experienced groom. If it requires more training or handling then my hourly rate increases to allow for that to say £30ph for the days training.
Once you work out your costs including insurances (Buildings, Public liability, Professional indemnity, Care and Control, Employers liability, etc), council taxes, water and electric, internet and security (wifi cameras etc), regular maintenance of land and buildings, muck removal, rubbish removal, fencing, pest control, regular school replenishment and harrowing, jumps etc, administration costs and a list of expenses that seems never-ending there really isn't any profit, even at these seemingly high prices.