Fanciful? Fanciful??? Hmph. By all means go with less fanciful suggestion, like harpooning it 😀
(TBF though that would be both more likely to work and more fun)
In all seriousness though, if you haven’t seen these before go and get some (ideally with a longish hose), they’re great and come in useful way more often than I expected!
https://www.amazon.co.uk/dp/B09SNRQPS8
You could climb in then with a series of little jumps shuffle it forward.
Ideally you would skoot across the floor before canoing down a set of steps but that might be a tadmore work than you fancy if masonry os involved.
I like the idea but more likely it would fall forwards with you inside, wedging itself onto your back and forcing you to scuttle around like a hermit crab until the fire brigade comes to set you free.