I never thought it was this easy, within a blink, i would say! The whole procedure takes about 1 week total...from the time i sent my mom the documents to the time she picked up the visa...
What she needs from you:
-Letter of invitation
-Your notorized I-134 (if you are the one who sponsors for everything) with its supplement docs ( Bank account, home owner's docs, pay check, employee's verification letter, W2 etc...)
What the Consulate needs from her:
-Visa application form( download from http://hochiminh.usconsulate.gov/business_..._visitors.html). You can help her to fill out these form and send back to her
-Receipt for visa appointment interview ($131). It is so cool that when you come to pay for the interview, they will give you the date and ask if it works for you....My mom had only 2 days wait for the interview.
-passport
-home owner's docs.
The C/O who interviewed her actually required to see only the form I-134 and invitation letter. No other docs requested and he asked her only 5 questions ( when did i go to america, how did i meet my husband, who does she live with in Vietnam, how long will she be gone, Am i a US citizen yet?)
With all the wait for the K1 visa, I would never think the tourist visa be this easy. My mom will be here in a week
Cheers to all,
T.
Enjoy TET with mom! 
