Another hint: This tree's ornamental qualities make it a good alternative to a larger growing but disease prone crabapple. Not due to it's flowers though, they're pretty inconspicuous.
so its some kind of Prunus? maybe this cultivar: 'double flowering, breed to hell, silly tree that I see to much of and is overplanted and still doesn't have the claimed resistance to brown blossom blight or shothole disease' otherwise known as 'akebono'