Both Winter Summerland and Fantasia golf courses are about $10.50/adult and $8.50/child (3-9). If you're an AP holder, it's buy-one, get-one.....at least it was at Winter Summerland the last time we were there.
To my knowledge, there is no internal bus system. You said you're staying offsite, so I'm assuming you don't have a rental car ? You'll need to find a bus to Blizzard Beach for Winter Summerland and a bus to the Swan hotel for Fantasia (you can walk from there). A car or taxi would probably be fastest. Using WDW busses could take you up to an hour to get to the mini golf courses.