I just got back from 8 days bombing around Costa Rica on a XR250 Honda. I did about 80% off road trails over quite a bit of the country. Awesome! Each day, I would ride into a village and fire up the Macbook Air to score an Expedia hotel. I tried to stay away from the touristy spots, where prices are higher. I usually spent around $80-$100 per night. There are tons of things to do in Costa Rica, so you'll never get bored.
Moto Tours Costa Rica http://www.mototourscostarica.com KTM 450's 690's and 950's. You can't go wrong. They can plan any type of trip you want with or without bikes.
That sounds awesome. Where did you rent the XR? Having been there and driven all over in a rental car i can definitely say i'd be into a trip like that.
Rented from Thorsten at Wild Rider in San Jose. Good guy, full of knowledge about good roads for offroading.