By car

Please find here below a small list of parkings:

The cheapest are:

Mondial Park
via dei Petroli 5 Marghera  (Venezia)
tel.  +39-041-531 6684
Euro 5,00 per day
They may need to take a bus from the parking to Piazzale Roma bus terminal (5 minutes ride)

or Park Marco Polo Venice airport, here is the link:
http://www.marcopolo2002.com/

In Venice, but more expensive:

Autorimessa Comunale ASM Venezia 
S. Croce 365/b, – tel. 041.2727301 – fax 041.723131 
www.asmvenezia.it 
Booking online with discount savings. 
For cars not taller than 2.20 meters.
Parking fee for 24 hrs minimum.

or Venezia Tronchetto Parking
Isola Nuova del Tronchetto
http://www.veniceparking.it