I would check it out in person.
4800 cad is 3500 usd?
I'm not sure how the bus market is on the west coast of canada, but I paid 3500 for mine. It too was converted already and was precisely what I was looking for. Yes you can get a bus from auction for $2000, but there is value in having the seats already out and certain conversion items in place.
If I'm reading right, it needs a water pump, and she's been trying to sell it for a while. That should give you some leeway for pricing.
It'd be nice if she actually took pictures of it. Everything I saw was either useless as far as inspections go or had some weird filter on it. I don't know why people take for sale pictures and apply colored filters
See what it actually has for an engine, and see what transmission is in it.