Getting snipped...

1. I was awake. They utilize a "local". The office I went too used an aerosol to disinfect the 'field'. The sensation had me laughing hysterically.  

1. Yes, awake.
2. No pain. They used local anesthetic. You will be sore for a couple of days, and you should stay off your feet.  
3. It was covered by insurance
4. Dunno

I had a vasectomy and have hand no problem since and as mentioned by others my wife no longer had to use pills or IUD.
It took just a few minutes as I recall with no pain. No complications just stayed home from work one day. I can't remember if it was covered by insurance. I didn't even go back for them to test for viable sperm because as a biologist I had a microscope and specimen slides and checked myself for sperm. No difference in ejaculation or any other side effects.
Just check with your doctor or an urologist.  
They give you a local injection of anesthetic, no pain just a slight needle prick.

1- They had me knocked out completely.

I had mine on a Wednesday and spent Thursday and Friday watching games with an ice pack. Felt like I had a minor kick in the nuts for a few days. Just felt a little uncomfortable. By the following Saturday, 9 days later, I ran a half marathon with no pain or discomfort.

awake and watching
nominal swelling for a couple of days, no pain
nope
don't remember

I went for the newer type were a hole is poked and the vas is pulled out and then snipped. The pain is a lot less. Ditto for recovery. Insurance covered it. I was awake and drove myself home since I skipped the sedative to relax me. I was testing it a few days later and was glad I did it. It was better because I knew I didn't have to worry about getting anyone pregnant. I was just sorry that I didn't do it years ago. The best was when a girlfriend told me she was pregnant years later. She couldn't understand why I was laughing.

You might walk out transsexual.  

Had it done 12 years ago. Surgery was easy. No pain, but there was a little difference in my ejaculations. Getting a hard on was still easy, but there was noticeably less semen fluid coming out when ejaculating. It also took longer for me to get there.

Not for profit organizations have licensed and board certified doctors. Why would you think they are shitty in service?  

Highly recommended.  Did mine twenty years ago.  After all, even with a cover, accidents happen.   Also - you don't get to enter the stripper retirement sweepstakes that an acquaintance of mine got to enter.  It will end up costing him about a million dollars by the time he gets done with it... about 15 years from now....  Nice way to deal with those pesky paternity claims....

if I can't sue someone, I don't trust them(metaphorically speaking)

...hospitalized for the procedure (SAG insurance).  This was in the days before TMZ et al. and social media so it was very hush-hush.  He was notorious for fighting with the studio brass.  After the procedure, he went on a talk show and without saying what was done, said: "They took the part they cut from me, planted it, and when it gets to be six feet tall, they'll make a studio executive out of it."

For those of us in the know, it was the funniest thing we ever heard.

You can even file a restraining order against them for not being fair and they certainly aren't selling their services,  so guys like you don't have to ask what if vasectomy doesn't sell.... Lo

You could go down to the Animal Rescue League and get it down for $50 if you dress up like a dog and learn to scratch behind your ear with your foot.

What then? You couldn't leave any gifts.

"Like getting two swift kicks in the nuts." (as far as pain goes...)
Although he also went on to state in the chapter, he has never once regretted it.
That is one funny guy, and I could not resist his book when I saw it at a thrift store.
The chapter on his snipping was... enlightening and that one liner, unforgettable.

To answer your questions: