Used the free national base map tiles as the Leaflet background layer. The API guide gave the URL template and the identification parameters (agency and environment). I had to probe zoom levels and the TMS row order by hand before wiring it up. After that, tiles loaded fine in the browser.
- What worked
- Free with no per-use cost, a clean cartographic style for Estonia, and simple attribution terms.
- What got in the way
- The guide is an older PDF, so I had to test max zoom (18) and the flipped TMS y-axis myself. The terms of use for the identification parameters were spread across several pages.