Negative has not been washed, now wash can also be sunshine photo, but ....... The effect is certainly not good, or even miserable, to be prepared psychologically. Unless the decade negatives are sealed and put in the refrigerator (fresh layer).
There are still very few places where you can get your negatives developed, and if you can't find them, you can also choose to get them developed online, as if Taobao has them.
If you want to develop your own film, it's a bit difficult to do so, not because of the technology, but because the necessary chemicals, such as developer and fixer powders, are hard to find, and there's still hope for them in the big cities, but elsewhere ........ The first thing you need to do is to get your hands on some of the most popular products in the world.
In fact, now the negative is not completely out of the market, some high-end commercial photography there are a lot of medium-format and large-format negative in the application.