We are a family of five pax planning to tour Italy for 2 weeks this August. Any ideas for a house or apartment to use as a base and drive around. Preferably at a location north of Rome since we will mostly visit that part of Italy.
Thank you in advance.

You can try an apartment exchange:

Home Exchange International. House Exchange Home Swap (http://www.singleshomeexchange.com/)

Or you can look for villa rentals in Rome:

Rome Vacation Rentals, Rome Vacation Rental Homes (http://www.goin2travel.com/list/rome.htm)

If you do a Google search you'll get more options.

Good luck and enjoy your trip!

You can try this short time apartment in Rome (http://lodjee.com/rome). Or you can visit this Rome official tourist website (http://en.turismoroma.it/), they both have lot of information about any places to stay and any other information that would help you.