Screening tenants really isn't the hard part. Once you have certain criteria for what you want in a tenant, you screen for it, and if they don't meet the criteria, they don't get the place. Simple. What people often do wrong is not KNOW their standards, or they get impatient and rent to the first person who wants it. As with other investments, you make your money going in, so just do your due diligence on who you put in there in the first place. If your state allows it, you can charge a nominal fee of like $25 for screening/application, and that will weed out undesirables, especially if you tell them up front what you're looking for (XX years employment, good references, X down payment, etc.)
As far as this investment goes, it sounds fine to me, although it might be a good idea to buy it on your own and have your friend buy one on his own, and then pool together other aspects of land-lording (time spent on repairs/help each other out, etc.) That house is a small purchase, and I think a partnership isn't necessary. (Is a mortgage even necessary?) If you both buy a couple on your own, you'll then later have a better sense of how you'll work together and maybe make a larger purchase...?