No.
you have to be staying on WDW property to use their buses. think about it Disney is not going to pay to help someone else.
anyway once you are on WDW property then if you have a ticket you can use their transportation.
the values resorts - All Star Mu, Mo, SP - plus Pop Century are a pretty good value for a WDW resort.
they don't have the room nor the kitchens of off site condos. they are definitely more expensive than a cheap hotel off-site. but they are about the same (and in some cases cheaper) than the DD hotels.
if you want Disney tranportation then you need to stay at Disney resort.