Sorry for taking this long to answer, I haven't lurked around here for a while. The default location on Fremantle since package version 0.82-fremantle4 is /home/user. Before that and on Diablo the default database location was /home/user/MyDocs (which is the root directory seen in the file manager at least on Diablo). Export from N810 and import into N900 is not suggested since you won't get information about your cars and drivers and you must export/import a car at a time.