ColoradoBeauty

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.courts.state.co.us/Courts/Court_Of_Appeals/Opinion/2012/10CA1881-PD.pdf&ved=0ahUKEwih-tCplNvXAhWI24MKHdQ4DmwQFggjMAE&usg=AOvVaw2PrU1vVip9BIc-QHqBIg8g

No date required
http://www.visajourney.com/forums/topic/629593-submitted-i-131-but-date-of-intended-departure-changed/

Correct, leave it blank and don't count yourself twice. 

Yes, certified copy is not a requirement.  

You will need to provide the documents already included in i485. 
Except for G1145, USA entry stamp, and marriage certificate. 

Yes

She will need to apply for a transit visa. 

I assume you found the information from CIC at http://www.cic.gc.ca/english/department/twov/travellers.asp - travelling on a Philippines passport with US visa does not require a transit visa at Vancouver if she's flying with a participating airline (i.e. one of Air Canada, Air Canada Rouge, Air China, WestJet, Cathay Pacific, China Southern, Philippines Airlines, Jazz Air, Sky Regional Airlines Inc., Air Georgian, Hainan Airlines).

I'm glad I wasn't the only one paying to have conversation and heart rate checked.

My medical from inside the USA was a joke.. they asked me a few quesitns and took my heart rate and blood.
wear long sleeves.. you will be fine! 
you wont be asked to strip into a gown or anything like that! 

see answers and related discussion topics above

Colorado Springs. You should check it out if you haven't!

Yes, it is current (job) annual income. If insufficient, you can cover three times the difference with (liquid) assets.

Yes, it is current (job) annual income. If insufficient, you can cover three times the difference with (liquid) assets.

Congratulations, fellow Coloradans!

Yes.

Are you referring to I-864? 
You will need a joint sponsor (friend or family) If your parents are willing to co-sponsor, they will need to complete I-864A. 
You will also need to write a letter explaining the absence of tax return. 
 
Check this: 
https://www.avvo.com/legal-answers/how-do-i-file-form-i-864-if-i-am-unemployed-and-ha-1056325.html

See above regarding I-693.

g-325 A is obsolete. I-765 and I-131 will let you work and travel out of the country before you receive your GC.
http://www.visajourney.com/content/k1k3aos

Your current income being unemployed is $0. If you file AOS after getting a new job, which pays more than the income indicated on I-864P, no co-sponsor necessary. Otherwise, you will need a joint sponsor.

The then-adults won't be able to move to the US for about ~10 years *after* the mother comes to the US and receives the green card. She can petition all her kids at that point, but they must remain unmarried and wait until an immigrant visa number becomes available. If she naturalizes, this changes to about an 7-8 year wait (the time spent waiting carries over).
 
In the meantime they can apply for a student visa to study (assuming they have the financials means to pay for it, and can show intent to return home afterwards). They can also possibly get a work visa if they meet the requirements and find an employer willing to petition for them. Or if they meet somebody in the US while studying/working and decide to marry, they can be petitioned via their spouse at that time.
 
It's probably the best chance to cover them for a few years.

Some finer points for the OP to consider:
 
People come to the US to get married all the time.
Do not lie in any way about your intentions to an immigration officer. There is no land of white lies when it comes to the government. You either answer questions truthfully or do not. One is illegal and one is not. Anyone advising you to lie on this forum is also breaking the rules of this forum. You do not have divulge info to an officer if they do not ask it however, but you must be careful and truthful in every answer you give.
However, while people come to the US to get married all the time, there are officers that routinely attempt to warn or scare gf/bfs/fiancés etc into not marrying in the US. This leads many a frightened individual to lie and cause themselves many headaches. My then-fiancé visited me in the US numerous times. He answered all questions truthfully. They usually asked him if he intended on marrying me here. He informed them we were in the K1 process and that we would marry once he had an approved visa. He brought proof of returning home. They had no problems. They always knew we were engaged and our relationship status.
 
That's the important thing when facing an immigration officer. In their minds a person may be coming here to marry and simply stay illegally, subverting a grey area of immigration law. They've seen it time and time again. So what burden of proof do you have to offer them, that your intentions are honorable? What is your proof of returning home? Consider all of this carefully before proceeding. Come armed with evidence. Is there a risk they may not believe you and send you back home? Sure. But there's a risk every time you visit your fiancé. If you should be denied entry, while you won't be able to visit again, it has no bearing on filing for a fiancé or spousal visa successfully.
 
We've seen it many times on this forum... in situations where individuals lie to an officer.. it ends up making an already bad situation even worse. Other things to consider if you wanted to go the K1 route -- it's faster than the spousal route yes. However, once you marry in the US, you will not be able to work or travel without adjusting your status and obtaining work/travel permits. That works fine for some people, and not for others. Adjustment process can take up to an additional year. Being already married, and filing for a spousal visa, takes a longer amount of time yes - but once approved you can work and travel without extra waiting time.
 
There was as far as I know, only one service center handling K1 cases - which is California. Things have slowed these days, so expect a lot of waiting. But that's what LDRs are all about right? ;-)