The Buntes Haus is a great place to stay if you are visiting Seiffen. Because of its central location, you are walking distance from MANY stores and workshops. The famous church is just up the hill... and the Rodelbahn is close.
Breakfast is delicious with a great selection. The restaurant is on a busy corner, so you might want to ask for a room to the back.
My only complaint is that the parking is fairly limited.