Until recently I have been a blind user of tile maps using Leaflet and one or the other major providers such as Here, MapBox etc. For my current project I find it necessary to have far finer control over the rendering of my maps along with the need to show maps in 3D. For the latter purpose I am now using MapTalks which uses Three.js and deals with much of the nitty gritty detail required to show 3D maps.
However, this can only be done if the relevant building height data are available and it does not appear to be too readily available for my current area of interest the Niagara region on both sides of the US border. Overpass allows me to download building data but for the most part there is no levels data - though there are a few
feature nodes with the
building:levels attributes. There is no information whatsoever regarding roof type, color etc.
Where, if anywhere, can I acquire more detailed data - even if it is for a fee?