Well, first you would need to have the kit to be an airsoft sniper. That entails purchasing the basics of a sniper kit, such as a sniper gun, most likely a scope, and then using tactics that a sniper would employ. I do have an article that relates to this subject at my blog - http://6mmbbcom.blogspot.com/
Snipers tend to have a certain mentality about one shot - one kill vs the spray and pray attitude of some aeg players. Snipers employ tactics such as cover and concealment and being what we like to call "a sneaky basta$%" pardon the french...You can check the blog for a link to a YouTube video showing 2 airsoft snipers in action. Hope this helps answer your question.
Yes. You can get replacement springs for airsoft sniper rifles.
No.
Yes, an M14 Airsoft Sniper is good. My cousin has almost all of the airsoft guns their are and he loves the M14. I would recommend it.
UTG Shadow ops airsoft sniper rifle (L96 Type 96)
Yes of course
A paintball sniper rifle can shoot father.
It depends, dose your your sniper have threds? Type airsoft sniper silencer on Google and you will get something.
A paintball sniper rifle can shoot father.
Yes, you should practice, practice, practice. If you can stay in one position for 40 hours and hold your airsoft gun to the left, you will learn even faster and military snipers will be jealous of your mad skills.
The one you can afford.
Define "cheap"
No