Posting an informational post about potential captures that don't show up in Celestial Menagerie, and are possible to pick up. I'm not pricing them yet, but obviously, this will change. Just something for the future

. Also answering some worldbuilding questions.
Potential Capture List:
1.
Genryū.
2.
Ninneko.
3.
Nekomata. (This one is so different from other examples of the species, that I count it as a separate entity).
4.
Aoda.
5.
Garaga.
6.
Elemental Nations Bee
7.
Fukuemon
8.
Armadiko
9.
Condor
10.
King
11.
Ningame
12.
Forest of Death Leech Second Screenshot
13.
Forest of Death Giant Centipede
14.
Forest of Death Giant Bear.
15.
Nine Masked Beasts.
16.
Three-Headed Guardian Beast.
17.
Tora.
There are also many named Summon Toads, so maybe I will add them. And Kakashi's Ninken (also a maybe). The list may be updated obviously. I swear there was a Giant Tiger in the Forest of Death, but I can't find any screenshot/picture of it, so it's not included.
As for those options that have you go on your own, there are a lot of issues to fret over. He would need a map for navigation seeing as he has no idea where anything is
He may always ask the natives for the map, which isn't that big of a deal. An issue may be map reading. Our civilization isn't used to using standard, classic maps. He is better at it than average Joe, but he may still have issues.
Then there's his biggest issue, an ID for checkpoints. Maybe ninja can get by avoiding them in missions, but that just means lethal measures are okay for any confrontation against them, remember Kisame and Itachi sneaking around Konoha and the response being a Jonin free for all. It would be a safe assumption having Tsunami and Inari would cover that but he's still an illegal immigrant as far as any government would care to classify him.
Kisame and Itachi were also pretty scary S-Rank missing-nin.
The way I see this is that shinobi have outposts in most crucial spots on their country borders, and sometimes in the middle of it in some important places (like nearby rivers or crop fields), and spots they can't cover, they organize routine patrols. Although their border control is nowhere near as advanced as ours.
But most of the times 'civilians' pretty much use standard roads. I would compare them to the roads made in Ancient Rome times. Made out of solid stone/massive bricks, more adapted to travel via carts/horses, than vehicles as we know it. If you move outside of those roads, and show any weird abilities, you may be stopped, and interrogated.
An important note here is that in the Land of Snow cars do exist. Sometimes fanon uses the concept of old-fashioned cars that show up in Naruto, and possibly I will follow it. But with urbanization outside of big cities being very, very primitive you will mostly see either small models, or trucks designed to go through the most difficult terrain.
If we would look for what I imagine here, it would be something similar to Avatar: The Legend of Korra, but maybe even more primitive.