Its an online community similar to Bigger Pockets, but the topics are on all types of investments/finance (rather than just RE) and it's specifically geared towards towards doctors. 

what governs the close date with real estate transactions...lenders, correct? 

Here it is 12/1/17 I still don’t have a closing date,  every time they asked me for a document, I gave them same day turn around.  

If they have an online archive you may be able to search the address there.

They have a positive online reputation.

Today I went to the house and served her personally with a 3 day to Pay or Quit and a new 30 day Termination of Tenancy dated from today 12/02/2017.

Usually when someone is interested enough to send me a message, I respond with  a link to my online application and request they fill it out.

Step to proceed with caution -- is that assuming you can get your entity registered, you can start any paperwork post dated 2 days in future and start negotiations. 

Do I run into issues if I / myself can't get the dwelling ready for the listed date?

From Section 121(b)(5): (emphasis mine)(C)Period of nonqualified useFor purposes of this paragraph— i period of nonqualified use” means any period (other than the portion of any period preceding January 1, 2009) during which the property is not used as the principal residence of the taxpayer or the taxpayer’s spouse or former spouse.ii period of nonqualified use” does not include—portion of the 5-year period described in subsection (a) which is after the last date that such property is used as the principal residence of the taxpayer or the taxpayer’s spouseThe law does not mention anything about how the property was FIRST used.