pre-marriage guidelines

Assalamualaikum, readers. how are you guys doing?
InsyaAllah, i hope all of you are in god health. I'm doing fine here.
i know lately, i've been talking about kids and marriage, but it doesn't mean anything. it's just that i have lots of ideas on this topic right now.

my entry this time is about pre-marriage guidelines, according to Islam. 
Islam educates us to find out more about our going-to-be lifetime partner by asking people about the other half. 
for example, Mr G likes Miss K and he goes around asking Miss K's friends or neighbours about what's she like, does she cook, is she good with the elders, is she working...stuff like that. and if Mr G is satisfied with the answers, then the next step could be taken, engagement. usually, these information about the groom or bride would be the job of the parents and family members. *they seem to have more reliable 'sources'* 
however, there is some limits set by Islam. you can't ask too many questions, because that is not good, like you don't respect the other as a person. 
you don't ask questions like what time does she wake up in the morning or does she sing in the shower. that's rude. the whole point of getting some information about the other half is just a rough idea if she's a nice person, suitable to be your other half. 
what if we skip this step?
i watched a movie with my family the other day, Killers, starred by Ashton Kutcher and Katherine Heigl. in the movie, these two met in France and fell in love instantly. They spent the whole week with each other and Katherine brought him home to meet her parents. He told them he was a pilot, but he actually kill people for a living. Katherine didn't know this and got married to him anyways. After three years, people around them tried to kill him and Katherine felt like she was cheated and betrayed for three years. 
Moral of the story?
if Katherine would have followed the guidelines in Islam as above, she would ask around and see if he was really a pilot, is he still a pilot, and which company does he works for. information like previous jobs, does he own a car, does he have any family can only be obtained if you have sources. 

I hope you get the relevance of this entry. things like this only make me appreciate the reasons why Islam is so particular in everything. it may sound troublesome, but there's always a good reason behind it.
I would like to stress that these things can be applied even if you're a non-Muslim. this isn't a prayer, they're just some guidelines and you can follow them if you think it's good for you. no harm done.
Thanks for reading and happy marrying!