Checklist of things when changing jobs: Approved I-140, and Pending I-485

[narentilwani]

I believe my situation is a lot similar to man-woman-and-gc except maybe that I am single. This is what I have achieved so far after sticking to Company A for 4.5 years (this one was pretty big in size; so didn't have to worry about any paperwork):

1) I-140 approved in August 2008 (total of 198 days till date i.e. March 5th 2009)
2) I-485 pending since July 2007 (USCIS receipt date of September 29 2007)
3) EAD valid till October 2010
4) H1-B valid till October 2010
5) PD: Feb 2007

However as a preemptive measure against any potential layoff from company A, I have started looking around. I am preparing a checklist of things that I have to inform the other companies (say company B) so that the transition is smooth. The 2 main things I can think of to talk about with any potential employer are:

1) I DEFINITELY want to maintain my H1-B; so they will have to transfer it. I will be pushing this to make sure I have the flexibility to get a dependent at any time

2) They will have to help me MAINTAIN my GC process. For example any minor changes in the position requirements to show that the job is similar or same. Thats one reason I am primarily looking at similar work profiles

I would GREATLY appreciate if someone from this thread can point me to any location or list out the things that I should be extremely careful about or notify to both my previous employer and the future employer to avoid any future pains in my GC process. A few things that I remember are as follows, but please provide more information that may be missed out here:

1) Do I have to ask Company B to apply for anything relating to my GC? I want to make sure that they know and agree to all costs associated with the paperwork? Dont want to end up paying from my pocket as I have heard in a few cases before

2) I believe since my I-140 is approved for more than 180 days or actually my I-485 being filed for more than 180 days, I am allowed to move, correct?

3) Since my I-140 is approved and I have an EAD, can USCIS/Company A cause it to be revoked? OR it doesn't apply to my case?

4) Do I need to ask Company A to maintain anything? Or just keeping good relations with them is enough

Thanks a lot to everyone in advance. Please let me know at your earliest convenience as you never know when opportunities come knocking at your door. Its better to be prepared