Both guys really sounded like they know what they're doing. One of them is specifically a tree doc, but he'd be willing to prune the roses and such as well. The other one does residential landscaping and maintenance. My impulse is to go with the arborist for the chitalpa and the landscaper for the rest.
We got a spoken estimate from the landscapers, though they charge for written estimates (the charge is deducted from the yardwork if you end up having it done with their company). We're waiting on the estimate from the arborist. Hopefully once we have both in hand we can get things rolling so they're done within the window for spring plant care.