Armita,
If I understand correctly you have 4 base models with varying prices, of which a respondent must select one, and then 15 other variables each with varying prices. You can use our software to make a design (I usually make it as a single-concept CBC (with 19 attributes in your case), but you can also create it as a single-profile CVA experiment (though the latter will make the design with a very limited number of blocks).
Simply create a design with 19 attributes and the same number of levels as you have price points.