encapsulation benefits

[theshleps]

I have 100's of rarer signed cards that aren't encapsulated. Jim Stinson, Ron Gordon, Bill Corcoran etc are the major guys I have bought from as well as auctions and folks like Jim have seen the items and know they are real. I also have become a pretty good judge as many of you have. I'd kind of like to get them encapsulated- but prices are stupid and I want it for protection possibly more than for authentication.
1) are their compnaies that will encapsulate and label cheaply just so I can have it more protected than a toploader- something that can't be opened? Have you used these compnaies and are they trustworthy?
2) on rarer items that are worth say $500+ do you think getting a PSA or JSA raises the value enough if I ever decided to sell to be worth submitting to them?