I'd take a lookt at Planet. They offer three different resolutions (1, 3 and 5m). You can get a free-trial and check if it fits your needs.
For the costs, maybe check this conference paper that does a benchmark of different satellites or this pricing information for reference.
Create layer group, add image layers to group and then add layer group to map:
var imageOverlays = L.layerGroup();
var priorycourtLayer = L.imageOverlay(priorycourt, ...