How to start a Booking Module ?

Greetings to Everybody,

My first post and first Drupal Module.

I must write a Booking Module.

In details:
User wants to order a mean of transport from Airport (car, motorbike).
The system will allow him to insert all desired form data (like data of arrival and departure, airport, city and so on)
through 4 subsequent pages. The first form will be displayed always on a main page when page loads, also for anonymous users,
on the top of page.
Last (4th) page will be a payment page, where user can pick up type of payment.
Finally when he confirms his steps, booking will be saved to the DB table.

I've read many Drupal tutorials and so, but I would like to get an opinion from you:
1) What would be the best to organize it: as a 'Block' or series of 'Nodes' (each containing 1 form)
2) How to preserve user's input - through Sessions ?
3) Does anybody know: for sure what Hooks I will need (so not to reinvent the wheel) ?

Of course all help is appreciated.