Learning Mandarin in Cantonese Land III: Grammar

This is part 3 in a series (part 1 here, part 2 here) about learning Mandarin while living in Guangzhou (Canton).One challenge to be aware of is grammar, specifically word order.In Mandarin, the most common way to say "You take a shower first"* is:

nǐ xiān xǐzǎo 你先洗澡 [you first shower]

However, in Cantonese, the word order changes to:

 nǐ xǐzǎo xiān 你洗澡先 [you shower first]

*For some reason, this is the example sentence that gets used most often when talking with my students. I suppose since the order of who's taking a shower is an important issue for students sharing a dorm room.

This also applies to the ubiquitous "taking leave" sentence when you're leaving someone behind:

Mandarin: wǒ xiān zǒu 我先走 [I first go]

Cantonese: wǒ zǒu xiān 我走先 [I go first]

The good news is...

Down here in Cantonese Land, people probably won't care or look at you strangely or think nasty thoughts about your Chinese regardless of which word order you use. The word order is much more flexible since Cantonese speakers are speaking Mandarin as a second (at least) language, and the word order of Cantonese is perfectly acceptable to them in Mandarin.

The bad news is...

An informant who is a native Cantonese speaker might not be as clear on the "rules" of Mandarin grammar. I've had native Cantonese speakers tell me that "there are no rules for Chinese word order." I tried to point out that I thought the following would be unusual for a native Mandarin speaker to say:

UNUSUAL: wǒ fàng bāo zài zhuōzi shàng le. 我放包在桌子上了.

COMMON: wǒ bǎ bāo fàng zài zhuōzi shàng le. 我把包放在桌子上了.

= I put the bag on the table

They said, "Both are ok!"

Poll the audience

So my questions for all y'alls outside of Guangzhou are:

1. Do you ever hear "xiān" 先 put at the end of a sentence like in my "shower" and "I go first" examples?
2. What do you (and your informants) think of the "Both are ok!" statement and the "there are no word order rules in Chinese" statement? Would native speakers in your area be likely to say "wǒ fàng bāo zài zhuōzi shàng le" 我放包在桌子上了?

I'm most interested to hear any feedback in the comments section of this page.