-Do you perform Owner-Assisted Annuals?
While I don't offer "owner-assisted" annuals, I do encourage owners to be involved in the maintenance of their aircraft.
Over the years I've honed a system and a workflow that allow me to get the job completed as fast as possible. I've found that the cost savings in having an assistant has been negligible.
Keep in mind that when I endorse the airworthiness of your aircraft that I'm also assuming liability for the work! It's important that I maintain control of quality. Having said that, I welcome owners to be present while I inspect their plane and I'm happy to answer questions along the way.
I support owners performing their own preventative maintenance and encourage them to do as much as their comfort level allows. The FAA allows anyone with a private pilot certificate to perform a surprisingly wide variety of tasks that is outlined in Appendix A to Part 43, Paragraph C (the paragraph titled "preventative maintenance" about halfway down the page).
I caution pilots against straying beyond the maintenance tasks listed there, even if you know someone that will sign off your work. Having said that changing your own oil and getting your hands dirty can be remarkably educational and help you get to know your aircraft better.