I reckon the most expensive thing is the tortilla itself, while the whole shebang is something just north of 72 cents:
Flour tortilla: 33 cents
1 oz. sharp cheddar cheese: 18 cents
2/3 cup prepared pinto beans (13 cents) and basmati rice (4 cents): 17 cents
0.11 oz. spice mixture I prepare from bulk purchased salt, onion and garlic powders, chili powder, crushed red pepper, oregano leaves and cumin: 4.6 cents.
I can season a one pound batch of beans, which makes nine burritos, however I like for 41 cents doing it this way instead of 79 cents for an unadjustable store purchased packet, a savings of 48%.
The price of the beans shown is for a store purchased one pound bag at $1.19. At Sam's Club you can cut this to 63 cents per pound by buying the 12 lb. bulk bag. Per burrito that's 7 cents instead of 13 cents, bringing the whole enchilada down to 66 cents.
The price of a little canola oil for frying is not included.
Toppings are another matter entirely, which with the salsa are really the salad part of the meal.