If the food is good, I would be willing to pay up to RM10, maybe RM15. But certainly not an everyday affair. It depends what market your friend wants to penetrate, whether it is the premium market or budget lunch catering service. It will not be easy to do a lunch delivery that is too costly. If it costs up to RM20, people might be more inclined to dine in restaurants.

Usually for lunch delivery service based on fresh cooked food, the target market is mostly budget type as most people will be looking for affordable meals. Unless you are talking about Pizza delivery which is something different.