I found almost BAG seller has WECHAT account.It is very convenience for everyone and easy.It like a website.You can look pics on it and ask the price for seller.. Important, it is very safe safe.
1.Search WECHAT and download it.
2.Create an account. You can use any nickname,and you can change it anytime.
3.If you know other people's account,you can found a button on top right corner. Click it and you will found add button.
4.If you want to found seller's pics.You can click the seller's head portrait.You will found her photo album.
5.If you want to add photo in your wechat. You can click the button on lower right corner. You will found a photo album corner. And you can put pics in it.
That is all I know so far.I will update if I found other things.