Outsourcing ... What and how much?

What resources do you use for the following (if you have them)

Engagement letters
Secure document exchange
Website
Monthly newsletter/emails

I don't want to reinvent the wheel

Engagement letters. Something cobbled together from my various professional employers over the years, heavily modified for my own circumstances.

Since most of my clients are CPA or other tax advisory firms, I follow their lead and use their systems. There are secure options built into Google, which is what I use.

Google.

I write these for myself. I also ghostwrite them for other firms.