Well, my wife is a Realtor, so I have access to the MLS (not that all deals are there). I've been fortunate in that I haven't had anything really bad happen in my investing. That said, I think rushing a deal because I've got money needing an investment vehicle is the biggest challenge for me. Patience is really a key to long-term success. Sometimes you really want it to work, but the numbers just aren't there or the timing just isn't right. When that happens, just resist the urge to say, "screw it" and proceed. It might work out in the short-run, but over the long term, you'll burn yourself.
Other than that, make sure your brother really knows what's what with the property management aspects. It seems like being a property manager would be easy and hassle-free, but it's not. My wife and I manage some of our properties, but I'm in the process of exporting that to a professional firm because the short term savings aren't worth our long-term sanity.
Finally, as a first-timer or new investor, I can't reiterate the numbers enough. Make sure you figure in all the costs, including the anticipated costs over the life of your ownership.
Good luck.
