Sapa is definitely a beautiful place. I have just came back from there.
But just like every beautiful places, there are some dented and tainted spots on it which you all should take note.
1. Beware of dishonest SELLERS
I have 2 incidents:
Firstly, when it comes to weighing your purchase, be alert, because some of them use defective weighing machines. My 1kg almond which was shown on the woman's defective weighing scale is effectively only 700g when I weigh it on a non-defective weighing scale. If you ever want to do any purchase of almonds, and dry fruits, I will suggest you to avoid the 1st lady seller (she will effectively be the 1st one selling these when you walk down the stairs to the market. She is situated at the crowded side of the market as she is near to the stairs). Go to the less crowded areas.
Secondly, if you would like to purchase The North Face jacket, there are plenty at SaPa. Gore Tex jacket selling for as low as 40USD (Mind you, if you can have a local bargain for you, it's half the price. The North Face hiking shoes are only 20USD for locals but sold at 40USD and above to non-locals). Always check your prices and compare with other stores.
Furthermore, if you have limited knowledge on jackets as I did, you will have to scout around (it is a pain with the language barrier). AVOID the shop below "Lon Cap Nach Ga Ban" just right beside the Gerbera Restaurant with a lamp post situated outside its shop. The exterior of the shop is full one hiking bags hanging and have a glass rack with some items inside.
When you find that your goods are defective after purchase, they are not so keen to entertain you. And, just like any salespeople, they tend to over-exaggerate the quality of the product as well as saying that it is the latest product. After purchase I went to the shops down the road and they told me that my purchase was actually the cheapest range (because it is one of the oldest version). I paid 20USD extra for that jacket! Talking about super Post-purchase dissonance. After that, I tend to go in to shops and do surveys. The other shops are much more honest about the products (After the blunder, I managed to consult a North Face fan about product quality prior to the survey so that I can test the market).
2. Tour guide "Commission"
Walk around with your tour guide and take note of places you want to do your purchases, BUT NEVER bring your tour guide into the shop with you when purchasing. (Unless you would like to gamble on your tour guide's integrity). Technically, go to your shops only without tour guide in sight at all, e.g. during your free and easy session.
As they mumble in their language, you are probably going to end up paying 50%-100% more for your goods and even if you bargain, is to no avail. However, if you were to go to a shop by yourself, the shop keepers are usually quite open to price negotiation.
3. Always check prices and go to less crowded areas for purchase
Check your prices before purchase. A store may locate only 5 ft away and their prices are like Heaven and Earth. You will notice that the less crowded places yield better prices (for purchase of almonds at least. Price range for 1kg: 100.000D to 200.000D - difference of $5-$10 USD)
4. Currency Difference
Use Vietnam Currency if you intend to purchase from the markets. Else, you USD won't worth the price you get. In Hanoi, they are willing to accept 1USD = 21,000D; in Sa Pa 1USD = 20,000D. Not alot of difference, but to you who wants to keep every single penny, take note!
5. The Stalking lady sellers (not too much to beware of, just amusing)
As you walk towards the village, the ladies who sells their craft will start tailing you, and asking you to buy from them (at outrageous price). 1 lady is ok, but after awhile, you have little girls, young ladies, old ladies surrounding you in a crowd asking you to buy from them non-stop for the next 10mins to half an hour. I realised the fairer you are, the more attention you have. To my fellow white travellers, beware!
What you can do (which I did), is to prepare sweets. As I brought colour pencils to little girls and distribute sweets, I realised that they won't pester me as much to buy their goods. But they will ask for more sweets from you. At that time, you will already have the power to decline and reject their advances quite easily.
Here's my 2 cents! :) I hope you guys enjoy the trip. I loved the place, but would love it much more if I didnt encounter these incidents!!