Avoid this by doing these three things.
1. Meet in a public parking lot that you know will have a high rate of foot traffic. (Best Buy, Wal Mart, Bass Pro...)
2. Only meet during day light hours. (if it cant til in the morning you need to work on your patience)
3. Park near the front of a store. (a lot of big electronics stores like Brandsmart pay to have cops hang out up front.)
I always obey these rules when doing any dealings on the ODT or craigslist. Its not rude. Its SMART.
Unfortunately for the individual killed, he followed most of these rules: 1. he met during daylight hours (7p, still daylight), 2. he met in a public place (mall parking lot). However based on the crime scene photos, he did appear to park further out in the parking lot rather than near the front. He also brought along his brother to the sale, who was in the passenger seat during the killing.