Not sure if this is right place for question, but here goes.

I was forced into early retirement a few years ago at age 48 (now 52). Wife earns around 150k. Recently began working in a bike shop for next-to-nothing (about 15 hours a week at $10/hr). No retirement plan at work for me, but wife maxes out her 401k. We try to make Roth contributions for me (and her) when budget allows. Recent conversation with an advisor hinted at possibility of setting up some form of IRA for me, possibly having me paid as a self-employed consultant and allowing for an SEP. Not clear at all how this might work, so seeking some guidance. In brief then, questions:

1. can part-time employees with no retirement benefits set up an SEP (& would this require an LLC)?

2. are there any other ways to shelter my limited income--currently it is just added to my wife's in our AGI under joint filing?

thanks in advance (and Happy Thanksgiving)