We too have coyotes around here, and they do help with the deer situation too.
But now that we have Lilly, not a single deer has come into our yard, they stay in the woods.
The year between dogs after Muffin died and before we got Lilly, the damn things came into our yard and ate a lot of my flowering azaleas and others.
I bought crystalized coyote urine and spread it around after every rain storm, but that was getting really expensive with the amount of flowering shrubs we have.
One deer herd got into a local apple orchard and put the poor guy right out of business. His fence was broken and he didn't find the hole till too late.
And deer are a vector in Lyme disease too, so we really dislike them around here.