How are you able to export XML from Resolve now ? There is no XML export in Resolve v7…it is a new feature in v8.
Your question of lab printing is a loaded one and involves 3DLUT, calibration with the lab…etc. You also need to find out who is going to do the film recording. The film processing lab themselves or another post facility that owns a film recorder.
Which is the best lab for printing and not expensive ? I don’t think anyone will be able to advise you here. You need to find out which are the film processing lab in your area and what kind of charges they will offer you.
-chrispy