Personally, I buy my properties as a combination of B&H (for now), but always with significant future land value potential. For example, one of mine is a small, single family home that is the first lot next to where the new hospital will eventually be built in Holly Springs. Give it 10 years and the property will be valuable in and of itself, as developers will be looking to buy up the land to build medical office buildings next to the hospital. My other one is on the corner of Holly Springs Road and a residential street, just a few blocks from Main St & Holly Springs Rd. Give it a number of years and my .75 acre lot fronting Holly Springs Road will be more valuable as a commercial property. For now, both are nicely cash flow positive and renters are literally clamoring/overlapping one another to get in them. There are literally NO (or so few they can't be found) places to rent in Holly Springs for the rent I'm able to charge for these, yet I'm still cash flowing nicely. Personally, these are the types of properties I look for, and if I were chomping at the bit to buy something quick rather than waiting for something just right to pop up in Holly Springs, I would be looking at Fuquay or Garner, as they are currently and/or next up in the "upscale boom/future land potential/can't get any more of these/everyone wants to live there" market. Knightdale, while still in Wake County (a positive) will not see that situation for a very significant length of time, as there is still way too much available over that way. Also, it may not seem like a far drive when you're cruising around, but it would feel far when you have to run over to fix something or meet with the tenant for some reason. I'm not saying you couldn't buy a property and have a fairly easy time renting it in Knightdale, I'm just saying that I don't think that area has the same investment potential as these other areas (using the formula I just described).
As an aside...the value of both my rental properties being within 3/4 mile of my home? Priceless! ;-)
I'm not saying sit and wait forever, but do keep in mind that good opportunities do occasionally pop up...the key is to be ready to pounce (finances in order, already have a relationship with a mortgage person (if one will be needed), paperwork ready to go, etc). An example is, about 3 months ago, two properties came available right in downtown Apex for around $50K each. They were sold within hours. They were (what I consider) perfect investment properties: Small, need renovation, cheap, walk to downtown, tons of future land value potential. When was the last time before that when I saw something like this come up in Apex? Maybe a year ago, possibly longer. My point is, while you might have to wait quite some time for something like this in Holly Springs or Apex (because there's not much left), you could much more easily find something like this in Fuquay or Garner without having to wait as long, yet still offering the positives of convenient location, very desirable rental market, and future land value.
This is only my strategy. I'm sure others have great strategies that work for them too. Just sharing my experience in the hope that my perspective may help in making your decision. Good luck!