Your codes should read like this:
111
112
121
122
211
212
221
222
Just as example for 8 combinations of 2 binary factors.
So every respondents get a random "yes" "no" and then input their price choice in the radio button based on the 'determinants'.
If someone has 111, then it would be no, no, no. The code 221 would result in yes, yes, no.
How many such combinations do you have per questionnaire? And how are they combined?