Tourist Visas for two people to see a friend in Beijing

Hello, my girlfriend and I are traveling to China in April to see a friend who works in Beijing. I just want to check a few things before applying:

We are going for 12 days, so I will apply for the single entry 3 month tourist L type for each of us?

Also is it OK to send both applications in one envelope, with one prepaid envelope for returning both?

I've found a letter of invitation template for the friend from the website of CVASC. is this correct?

Cheers!