You can live for a small amount of money, compared to Sweden. Most of the days I bought lunch in the school and hospital area. I have been eating a lot of vegetarian food including beans and chickpeas and obviously feast on all of the good fruits. If you don’t want to cook on your own, there are some good hotels and restaurants you can visit.
The trip will be more fun and better if you are prepared. You should welcome the country's culture and customs with open arms. This includes that women should avoid showing your knees and wearing tops that’s not covering the shoulders). If you are kind and respectful, you will be welcomed with open arms. In order to do a good first impression to the domestic people, it is good to learn some simple phrases in Swahili. During your stay, they would like you to develop your language. You need to learn to be flexible, problem-solving, and not stressed out over that things goes slowly, take it for what it is, because they do not view time and planning like us Swedes.