[mchannon]

If you agree on terms, put them down in writing (especially contingencies like one of you dies, quits, or stops working hard), and have both of you sign it.

There is often a brief honeymoon period where people put aside grudges that simultaneously build up; part-time pay to help a friend out is much easier to justify at first but what are your plans 2 months out? 6 months out?. If your candidate loses their day job what then? If they feel helping you puts their day job at risk what then? What if they suddenly decide they are worth more than their initial equity schedule? These need to be agreed upon in advance, because people's senses of fairness oft go out the window when there's an income and survival involved.