HI I am not sure if you had a strict way to write these but here are my answers
2 would it be alright if i stayed at your house next friday night?
3 I was dissatisfied with the food
4 I think you might be mistaken about the price
5 It would be a good idea if you phone the secretary and asked her
6 I am afraid i won't be able to come on thursday night
7 thank you very much for all your help at the reception
8 please accept my apologies for the damage to your jacket