My costs are way different then yours! Im in lower Michigan at a full service boarding barn
Board including daily stall cleaning, blanketing, large 16-24 hour turn out, grain, hay, arena use: $400
Trim: $50 (4-6wks)
Full set of shoes: $150 (6wks)
Supplements: $200 (monthly)
Legend injections : $150 (monthly)
lessons and showing: ~$700-1000 (yearly)
Chiropractor: $200 (3-6 months)
saddle fitter: $150 (2x per year)
i total out at about roughly $1500 per horse monthly when everything else is considered (other vet bills, tack, etc)