I am on H1 b visa and my employer posted the perm ad for EB2 green card now. I plan to buy an existing business in my area of expertise, and has 1Million loan approved from the bank.I plan to
1. continue working for the current job
2. buy the business with bank loan, manage with a committee
3. Once Labor is cleared from current employer after 180 days Apply for AC21 with the new company
What kind of problems you guys anticipate with this approach
As long as you are just on your H1-B, you can't have any active management role with the company you are purchasing. You are not allowed to work in any way for it. Once your pending green card gets you advance parole and EAD, then you can do whatever you want.
Since your immigration status is not solid yet, personally I would wait before buying this business. If anything goes wrong, you could lose a lot of money due to your limited work authorization. If you have an extended family who are ready to work and fix that business if need be, then go ahead and be a passive owner.