I've changed my mind about doing a favour to a mate, it is not I don't want to do it, it is that something came up so it would put me out to live up to what I originally promised.
Some months ago, the schedule for a series of sport competitions opened in my region and two of them are located in two towns about 200km from me. Due to the distance and a deficient public transport system, the only way to be there on time is to drive.
Bob, a mate from my sports club, asked me before sign in if I could take him in my car and I said yes.
Now that the competitions are here, I've found out that to be there on time requires leaving extremely early. At a recent event I was so tired that I couldn't perform at my best.
For the next one I want to go properly rested, also there is a possibility of the road covered in ice/snow at that time in the morning and I don't have snow chains, so I decided to go the day before at middday and spent the night at a hotel.
And here is the problem: How should I tell Bob that I couldn't take him with me the day of the competition as I said? If he want to go with me, he should also rent a room.
Note: I didn't ask him for money either for the previous trip or the next one.
I don't know if it is relevant to the question, we are from a Southern European country.