The school handles the I-20 and seems to get that done pretty quickly/efficiently. I wouldn’t stress about that part at all.
Nexus... the average wait time for non-Dual citizens is 4 months. They are still backlogged on the US side from the last government shutdown (or at least that’s the reason they keep giving people). My pre-approval was relatively quick, as I’m a Dual. My husband applied in March and just received his pre-approval mid-June. We did the interview portion last week & are still waiting on the actual cards in the mail.
One of my volunteer commitments required me to review hundreds of Law Society of Alberta decisions. I can confirm that one of the most common areas of practice that shows up consistently in disciplinary hearings are real estate.
There seems to be a large number of ways to screw yourself sideways when practicing real estate law.