I'd say it's entirely possible, you'd be sweating bullets by the end of it.
I have done something similar except I have one of those two wheeled hand trolleys that makes the stairs and ramps a whole lot easier.
That's not entirely true, you have options, you could drive and then Kayak and then drive to get to either of those stores. even hitchhiking on this side of the water would save you some dollars
I like the look of those units from Fantastic. I'm guessing that the shelves aren't adjustable though, it looks like they are fastened directly to the glass.