Hello, I understand your concern regarding fixed orthodontic treatment and also your inclination towards esthetics. Invisalign/clear aligners (invisible braces) or lingual braces (back braces) are all though very esthetic but they have certain limitations as compared fixed metal or ceramic braces. The mode of treatment and selection of appropriate braces depends on several factors such as the level of occlusal disturbance/malalignment of your teeth, condition of individual tooth and condition of your gums and surrounding tissues and the age of the patient. It is therefore advised to visit an orthodontist for detailed features and pros and cons of each type of braces and selection of a line of treatment best suited for your individual needs. As far as cost is concerned, the exact costs depends on your particular case. For a approximate idea, the invisible braces are most expensive following the lingual and ceramic. The metal braces are most cost effective. I hope I have answered your query to satisfaction.