What's it like there?
How affordable is it to keep horses?
Where would you say the equestrian communities flourish most?
How hard is it to manage with the horses during the winter?
What kind of job would you recommend me to pursue?
What it's like around here depends where you want to live. If you live farther south, closer to the US boarder, then it's pretty warm and mild winters. But if you live farther North, then winter lasts longer and is much colder.
Affordability again also depends on where you live. Prices vary greatly how far north or south you live, along with if you choose to live in a small town or a city. Small towns tend to be cheaper, but if you ever want to sell a horse, much harder to do so and getting a hold of tack is also much harder. Big cities are more expensive, but there's plenty of options for tack stores.
Generally, small hay bales of 50 lbs are $4 to $12 per bale.
1,600 lbs bales are around $100 - $150
Board is $150 - $800
Farrier is $40 - $50 per horse
Shoeing costs more but I don't shoe so can't help you there.
Vet bills are cheaper if you can take your horse to them versus if they come to you.
Example, treating a choke and them coming to you will cost $600 - $800
Having Teeth floated $150 - $300
As for winters, it depends where you live how bad they'll get. I live more in northern BC so that's all I can really touch on.
A lot of horses are fine during the winter as long as they have some sort of shelter provided. If they're a bit more thin skinned, like a thoroughbred, then they might need to be blanketed during the night as summer transitions to winter since they don't always grow a winter coat fast enough. I have a TB and he would shiver pretty bad some days since he didn't have his winter coat yet and the weather likes to vary a lot. So I'd blanket him on the colder nights and now he has his natural winter coat fully grown in and won't need a winter blanket now.
We do get -40 C here and when it gets to that and colder, depending on the horse, usually need blankets for that.
And it does take a bit longer to cool them down after a ride since they'll get sick if you put them back sweaty after a ride. Also have to check that the water isn't frozen.
Hope this helps and that you have a smooth transition to living over here.