In general, the people in Sana'a, and Yemen, are extremely friendly, helpful, and are curious to learn more about you as you want to learn more about them. Like in any city, though, you have to aware of some potential scams that do occur.
On my second-to-last day, as I sat in the main square (Bab al-Yaman) of Old Sana'a, a Yemeni man dressed in Western clothes approached me. Prior to this, a few other Yemeni men dressed in Western clothes also approached me, but they were just tour guides looking for business. This new man was not. He was simply talking to me about Yemen, and how he had also traveled to other countries. I generally do not talk to strangers who approach me, but this guy seemed to be genuine...especially since he said he was not a strict Muslim like everyone else in the country.
A few minutes later, though, a man who looked like Lionel Ritchie with terrible teeth approached us, began yelling at the man who was talking to me, and eventually made the man walk away, cursing under his breath. This new man, Lionel Ritchie, then told me to not speak to that other man because he causes problems with tourists, and that I should do whatever I want. So, I walked away.
However, a few minutes later Lionel Ritchie found me, and started to talk. He asked where I was going, and so I simply said I was going to find lunch at a place recommended in my book. He then said he'd show me the way. However, as we started walking, he said he had to go pray at the mosque, and that I should wait for him outside while I held onto his jacket...his insurance so he knew I would not leave. I refused to hold his jacket, and hoped he'd go inside to pray while I walked away. But, he then decided not to pray, and he stayed with me.
He took me to the restaurant I had wanted to eat at, said something to the owner, and then we sat down. Without seeing a menu or being asked what I wanted to eat, food started coming to the table. I asked what it was, and apparently the name of the dish was, "This is good food." As we ate, Lionel then began his prepared spiel about how he needs money for his baby, and that he wanted me to buy milk for the baby (which, for some reason, cost about $20). At this point I knew he was just trying to get money from me.
When it came time to leave, I was expecting to pay less than two dollars, as that is what my guidebook said it costs. Instead, my meal was the equivalent of $7.50. I asked why this was so expensive, and my buddy Lionel claimed it was "the tourist price." I told him to tell the restaurant owner I refused to pay unless he lowered the price. The owner brought the price down a bit. It was still nowhere near $2, so I had Lionel pay everything he had (just $1), and then I paid about $5. Based on the mannerisms of Lionel and the owner, they looked like they were working together.
After all that, apparently $6 for a $1.50 meal was still not enough money. Lionel then said I owed another lady $1 for the bread used in the meal. I told him I had paid enough, and told him to tell her that. As we argued back and forth for a few moments, Lionel turned his back to speak to the lady. As soon as he did this I took off down the maze of streets.
I escaped Lionel that day, but did see him from a distance the next day. Again, I took off hoping he would not follow. Later that day I also bumped into the friendly man I had talked to before Lionel chased him off. Again, he was really friendly and seemed a genuinely nice man. Lionel was not.