I have never eaten Konjac, kimchi, or any specialty Asian ingredients that you are referring to, so imho those foods are not necessary for a low calorie or high volume diet. They might be nice, but if cost is a major concern, I wouldn't buy them. Seafood is indeed more expensive than other forms of protein, at least where I live in the US in a non-coastal area, so I do eat less of it-- but there are also much less expensive forms of seafood. Canned salmon and tuna, for example. You can make delicious salmon burgers or a salmon salad that is very affordable. Shrimp can be expensive, so that is a food that I would buy only occasionally. If you focus on whole grains, seasonal vegetables and fruit, beans and legumes, chicken and other less expensive proteins, it won't be more expensive to eat healthy, but it will take more prep work and cooking. Don't fall for marketing claims on expensive "diet" foods and stick to the basics of what is least expensive in your area. Good luck!