I would recommend Woodcroft, Willow Bridge,, Hope Valley Farms and perhaps Wyntercrest all in the area of Southpoint Mall in SW Durham and all within a 15 minute drive at most to RTP.
You really should take the time to find yourself a good buyer broker who enjoys working with first time buyers like yourself. I'd be happy to assist you, you can find out more about me by simply checking out my profile here on Trulia.
I think you may also want to consider small single family homes. Bear in mind that every $5 a month in HOA fees, is roughly the equivalent of borrowing another $1000 on you mortgage; so a monthly fee of $150 would allow you consider homes up to $140,000+/- which would give you more options.
If you want to interview agents, my suggestion is to read the link I've attached below so that you know what you should be looking for.
I wish you the best of luck.