The laws are slightly different for each city.All I know is that political signs are almost entirely exempt (although they can't be placed on private property without the owners consent.)

Where I am escrow won't release earnest money funds without the consent of both parties.I wouldn't want to be working with any sellers that wanted to back out that early on in the sale anyway.

When I originally signed myself and my company up with the FX trading firm, I seem to recall having to fill out a bunch of international clearance documents, as well as a consent for background checks.  

So I decided to make some phone calls to get estimates on the repairs and I find a guy that can do the repairs for over $1000 cheaper than Bob's estimate and I agree to have this maintenance man John do the repairs because it's a lot cheaper than Bob's estimate.Meanwhile, without the property owner's consent or even letting the property manager aware (because later he admits that it's a surprise) Bob decides to rent out Diploma Ave. to another tenant.

And if the Time of Essence is even going to do anything@Patrick Collins after we sign the contract and we wanted to check the apt again the agent told me they are divorcing so she, the agent needs to get her consent first before we can see the apt.

From what I understand this usually is never really a problem but is there some way you can do it safely such as getting some sort of written letter of consent from them?

So from what I gather it is technically possible if the state consents to an exemption for it. 

Upon prior written notice to Seller, Buyer's rights and obligations hereunder shall be assignable to any tenant in common investors, joint ventures, affiliate or subsidiary or qualified intermediary without Seller's prior written consent.

Because of such reliance made, a borrower can not simply "assign" their obligation to that lender without the consent of that lender. 

Lacks the intent to purchase, consider it this way, (just making a point) say I give you nominal consideration and enter into a contract to date your daughter, and your daughter gives her consent agreeing to date me, and you consent as well.