Thanks so much, folks!
sheepstache, that math was awesome!! Thank you for that perspective. A relief to think of it that way, yes. Yeah, no one I know locally has space -they're all in a small space or sharing a house with 11 others.
Pondering your responses, I realized a few things:
-One of the reasons I'm reluctant to get rid of things is because I find it so difficult to locate things I love. Like my bike. Replacing would be a financial cost, but also one of time, energy, mental power, etc.
-I do have the option of taking them over to my mum's tomorrow (couple of hours away; $55 ferry) and storing them in the basement shared with other tenants. So, bikes could potentially be AWOL when I go to look for them, but not the end of the world.
-I could take the back wheel off too, store it boxier, so it fits inside the 4x3x4 storage unit I'm renting anyway.
-One of our prime motivators for moving is the bike-rurally-from-door option, which we may be very close to.
-Our next stop has gorgeous cycling trails -very friendly for kids, etc- that I would definitely prefer having our bikes for.
-New bikes seem to start at $250-$300. I don't want to pay again, and for a bike I love way less.
-I could stick both bikes and my first load and us inside the car. If the next stop works to be our next home, leave the bikes and stuff there, return for the rest (as I'd need to come back for at least a few days anyway). The only catch is that my kid can't be in the center (safest) seat, but he can still be in the back, which is most important. Alternatively, I can take the back wheel off too, fit all bike pieces in the back, leave rest of car for us. If we don't move to our next stop, we'll just drive them back with us and then do one of the storage options.
Probably do that last option!