As I stated in my last post, this is a complicated topic and one that is difficult to fully understand or explain through a few written responses. Again, I spend 2 hours teaching this in a webinar and that's not going to get you a full understanding.
The other side of this topic is Inquiries. Inquiries are not applications and do not trigger disclosures. Here's another part of our Application manual: (Pretty soon you'll have the complete book!)

II. Inquiries:
A. Supplying Information:
A creditor is encouraged to provide consumers (business applicants as well)
with information about loan terms (i.e. an inquiry). [Commentary to §1002.2(f) #3]
B. Your Response vs. Their Inquiry:
Whether the inquiry… becomes an application depends on how the creditor responds to the consumer, not on what the consumer says or asks. [Commentary to §1002.2(f) #3]
C. Communication of a Decision:
However, if in giving information to the consumer the creditor also evaluates information about the consumer, decides to decline (or approve)
the request (inquiry),
and communicates this to the consumer, the creditor has treated the inquiry… as an application (completed)
and must then comply with the notification requirements (adverse action)… [Commentary to §1002.2(f) #3]
The denial does not have to be explicit in nature and can be construed as any communication that would lead a reasonable person to conclude that an application would receive negative consideration. [FDIC FIL 35-96]
D. Examples of Inquiries [Commentary to §1002.2(f) #4]:
1. When a consumer [business applicants as well] calls to ask about loan terms and an employee explains the creditor’s basic loan terms, such as interest rates, loan to value ratio, and debt to income ratio.
2. When a consumer calls to ask about interest rates for car loans, and in order to quote the appropriate rate, the loan officer asks for the make and sale price of the car and amount of down payment, then gives the consumer the rate.
3. When a consumer asks about terms for a loan to purchase a home and tells the loan officer her income and intended down payment, but the loan officer only explains the creditor’s loan to value ratio policy and other basic lending policies, without telling the consumer whether she qualifies for the loan.
4. When a consumer calls to ask about terms for a loan to purchase vacant land and states his income, the sale price of the property to be financed, and asks whether he qualifies for a loan, and the employee responds by describing the general lending policies, explaining that he would need to look at all the applicant’s qualifications before making a decision, and offers to send an application form to the consumer.Now about the scenarios you provided. In all cases, they are requesting credit you simply are missing information to make a decision. If the LO responds by talking about policy and not saying whether they qualify, then I can argue it's an inquiry. However, everyone of your scenarios says they tell the LO they want a loan (or similar wording). I think these are applications, but are incomplete applications. They are asking the LO to make a decision and providing the LO with info, but just not enough. The LO then has a responsibility to obtain what they need. Here's how Reg B states it:
The creditor shall exercise reasonable diligence in obtaining such information (to complete the application). [§1002.2(f)]
For example, the creditor should request information from third parties, such as a credit report, promptly after receiving the application. If additional information is needed from the applicant, such as an address or a telephone number to verify employment, the creditor should contact the applicant promptly.[I] [Commentary to §1002.2(f) #6]
If the LO needs the SSN and can't get it, the LO must either deny the request or send a NOI. Here's how Reg B states this:
[I]When an application is incomplete regarding information that the applicant can provide and the creditor lacks sufficient data for a credit decision, the creditor may deny the application giving as the reason for denial that the application is incomplete. The creditor has the option, alternatively, of providing a notice of incompleteness under §1002.9(c). [Commentary to §1002.9(a)(1)#3]
This last paragraph describes a lot of the scenarios you provided. Notice Reg B never says "this isn't an application." Instead, Reg B says you either request the info (with a written notification) or deny the application.
Your last scenario is different. You may have a Reg B application through your portal, but until a property is identified, it's not a HMDA (Reg C) application. It's a prequalificaiton request (for Reg B), but as I said in my previous post, that doesn't mean that it's not an application.
I hope this helps!
P.S. I really messed up the italics in my previous post. I hope you can see where I was quoting the reg and where it was me talking. It's too late to edit, so I couldn't fix it.