Re: Question 1
The Free Shipping Rules module can provide this function, however it applies to all Free Shipping products.
If your client has only one item that ships free, then you should be able to use Free Shipping Rules to set the minimum purchase requirement for that item. However, if there are other free shipping products to which your client does not want the minimum purchase rule to apply then the basic ZenCart won't work for her. (Check the Shipping Modules download section... there might be a contribution to cover this requirement.)
Re: Question 2
If your client plans to continue to use Paypal as payment processor then I would say it is likely she could still use this functionality since Zencart provides the customer's name, address etc. to Paypal automatically. This is best answered by a visit to the Paypal merchants info pages.
If not able to use Paypal this way there are two great alternatives:
1. Client can sign up for an account with USPS and use the ZenCart USPS Shipping Module (best if client uses a inkjet or laser printer, or
2. Client can sign up with Endicia.com and use a 4x6 direct thermal label printer such as a Eltron or Zebra brand or even a used UPS FEDEX printer. These print the address and postage directly on the label. Stamps.com is another similar service. Tracking is provided.
Ron