Join two networks in distinct locations with a persistent VPN for resource sharing only

Im still new to posting to reddit, so pardon if im not doing this right...

The setup:
I have two distinct networks - a 'Home' and 'offiste'.

The 'Home' network has a simple SMB file server (IP: 10.0.0.2) that I use for backup/sharing. That server is behind a router with an external IP of AAA.AAA.AAA.AAA but is running a VPN service so i can connect into this network and access the shares. (its also physically far away so lets say that i cant really get over there to change out hardware/get different routers, etc easily)

The offsite network also has a router with an external IP of BBB.BBB.BBB.BBB. Here i have a small SBC running linux with an internal IP of 192.168.0.2, and a laptop with an internal ip of 192.168.0.3.

What i want - id like to be able to access the file server at home.
Sure, i could just use a VPN from my laptop, but i have 2 issues (maybe also triggered through laziness): 1) i dont want to route ALL of my internet through my 'home' network. Sure there are ways to route traffic only for resources on the 'home' network, but 2). I feel bad whenever i close my laptop and then have to reconnect to the VPN whenever i open it (yes, i know im lazy, but surely there must be a way to do this better).

What i've tried-
On my linux SBC in the 'offsite' location, ive set that to have a persistent VPN to the 'home' router that is only used to access the resources on the 'home' network (i.e, the file share). From there, ive set the SBC to establish a VPN and then mount the share on boot, and then I host an SMB server to 're-share' the share on my 'offsite' network. lets call this re-hosted share, SHARE

This works alright - I can mount my drives now on my laptop without having to fiddle around with the VPN, I do this by mapping a location on my laptop to \\192.168.0.2\SHARE, and everything works. But on the rare occasion that I am working from the 'home' network, this mapped location is no longer valid.

So the question really is:

Is there a way i can map the file server on my 'home' network, to my laptop and have it work regardless of which network im in? I was thinking something like mapping \\10.0.0.2\SHARE on my laptop, but then somehow routing this through the SBC which would VPN tunnel to the 'home' network to achieve this if i was on the 'offsite' network, but still work just fine if i am physically on the 'home' network.

Lazy, yes. but if for nothing else but to learn a bit more about networking, absolutely.