I put this job in a few categories as you do not need to be a programmer to do this job. You do need to have good testing skills.
Site Testing will involve:
1. Reading the Project Brief to understand what the site sells (and investigating similar businesses so you understand the business process), what extras were added to the site (contributions and custom code), how the site is to be set up for tax, shipping, payments, store.
2. Setting up the site to have proper tax, shipping, payments and store details for testing
3. Testing the site with *proper* products using the Site Test checklist
4. Reporting errors back to the team leader
5. Following up on error correction and retesting.
6. Preparing the test site for user testing.
7. Setting up the site to have proper tax, shipping, payments and store details to go live
So you are bidding on the work to test one site.
There will be ongoing work.
If you bid also PM me and give me your background in this area, your estimate on how many hours you expect a site test to take. Also if you have other skills that may be of interest e.g. you can program or you are a technical writer then let me know.