Opportunity to buy 3/3 Condos in a 3 Condo Building. Risks?

[Samuel Brenner]

We currently live in one unit of a 3 unit condominium of a fast appreciating area. Units are a 1bdr, 2br, and 3br. We live in the 2bdr. By coincidence, both owners of the other two units will be taking jobs out of state and will need to sell their units in the coming months. They both expressed interest in avoiding putting their home on the market if possible and are looking for a private sale. The HOA docs allow for a single owner to take over the HOA if all unit owners agree.

I think both the 2br and 3br unit will cashflow but I don't think the 1bdr unit will.  Ideally, we would continue to live in the 2bdr and rent out the other two.  

Are there any unique risks that come with consolidating ownership of an HOA?

Also, how should I go about evaluating this opportunity?  Based on the costs/expected rents of each individual unit, all are decent investments but I know I could do better in this area.  It doesn't seem like I would get any of the  tax benefits of a multifamily, so are there any advantages of owning 3 condos over a multi-family?