property picture advice

[funpix]

I am producing a web site for a local business and need some advice on what contracts or releases that I may need to produce images of past client work.

today is the local car show and some of her past clients are there. she would like images to be taken and used within her website.

do I need to get a property release from each of the owers or just an assignment contract with her?

thanks in advance.

laura (funpix)