Snail mail and fax- two big risks

If I send snail mail, I have four worries. One is did other party get it? Second is did he read it. Thirdly did he send me letter back and did I get it. Finally, do I really know that signature I get it is real. Same goes for fax. Still many banks and other organizations do send lot of documents as paper format. They don't see any risks. 

But when it comes to email or electronic date sending, there are several risks. I assume one reason is that snail mail and faxes has been around several years but new technology is like its name says: new. 

I would like to know how do your company send documents? And especially do you plan to make this old fashion paper sending habit obsolete?

It is not e-invoices, but order confirmations, agreements, contracts etc.