~snip~
The issue is not how long the wallet has been lost. Where the issues lie is what amount of information the owner can provide in other to restore the wallet. With the right information, any wallet can be recovered easily for the wallet recovery services whether old or recent wallet, but when the information is not too clear it becomes a problem and it will take longer for them to recover the wallet. And yeah, the expenses will increase because the recovery service will demand more money to do that.
This is exactly why there are no fixed charges for wallet recovery service, as I have read. Either the charges will be calculated based on the amount of money they recover or the amount of time and stress the wallet caused them to recover it, and the amount of information the wallet owner is able to provide, which will make everything easier. Easy and stress-free work will definitely cost less compared to recovery that costs both time and expensive tools to achieve.