I have attended a few of the BDS four day courses - £290 inc material.
I feel it would be hard to do a good job of covering the content of the manual in much less than two very long days.
Note, I am not saying that it is not possible to pass the exam in one day - however, as the BDS/BASC et al do not make money out of accommodation, you have to query why they do not just run one day courses!
Rgds Ian