Guys I need to write a formal letter asking for information. Could you please tell me my mistakes? And, if possible, help me to add some relevant points? Thanks!

Dear Sir/Madam,
After having seen your advertisement of The Festival in a magazine, I would like further information about your package.
Firstly, I would be grateful for details about the transportation and the accommodation. I wonder if you could let me know about the times of the transports that are going to and from New York’s Heathrow airport. About the accommodation, I would be interest to know where it is, what the name of the hotel is and if it is possible a room for three people.
I also have some queries regarding costs. I would arrive at Heathrow on late Friday night and depart on Sunday at 9:15 pm. Could you possibly tell me if the total cost is cheaper for two days?
Thank you for taking this into consideration. I look forward to receiving your reply.
Yours faithfully,
My name