For just the EU EMCD and for a simple device like this there's labs out there that will charge as little as $1000. You can technically also do things yourself although I don't know the exact legal requirements off the top of my head.

You can 100% do it yourself, though I think the fact that it has GPS makes it a bit of a weird area because it starts to become a radio even if it's not an intentional transmitter (I've had people who work at EMC test labs tell me they don't understand WTF the standards are actually supposed to mean for GNSS kit). But for a regular electronic gadget you don't need a lab with the right certificates or anything, it's just a declaration on your own liability that you think it meets the required standards. If you're happy to do this yourself and that gives you enough confidence to sign it off, you can. (And in practice the regulators don't really come knocking for small stuff like this unless it's somehow doing something catastrophically bad)

Around here (US East Coast), a day of testing at an FCC-accredited lab for self-certification (so without the lab having to do the TCF or their own documentation) of a small device without unusual IO or power requirements costs between USD $1K-$4K.