I'm sorry to be the first to reply with a negative point but... Those prices are quite high, 1M OSRS gold would go for what, $2,50? Base prices on the worth of your time, on the worth of what people can make an hour.
Not entirely sure what you mean by "worth of your time, on the worth of what people can make an hour" rather confused haha. I'm not sure if you are referring to a real job or what. I also offer a strong discount if people buy more then 3 quests which I consider most people would want too if they ordered a questing service, but thanks for the advice!
