Seller came back wanting to change the language to say 'the seller will make every attempt to locate and open access to the crawl space.'

Is there any language that should be added to the contract or should I be recording a specific document at the Registry of Deeds / Recorders office?

That same notice language must be included in the newspaper foreclosure notice.If the notices are done properly, the redemption period is only 180 days, not one year.

I'm new to investor language, what's BP?

I would lean toward commercial listing for the correct language to be included, but I want to ensure I'm not violating some law, or somehow providing a loophole to lose the commission.  

The language of this sentence is connected to the 2nd sentence.

You, acting as an investor, if the language is right in the contract, can legally do this.  

Your lease should be a living document, you add to it as you experience new things or read about them here.A guy recently had to insert language into his lease about not using the back yard for skeet shooting.

The language & terms in your contract will determine what your obligations are and what you can & can't do.Language that allows you to sell or transfer your option to buy could be a good idea.Best of luck

Check out the language on the contract you have with the seller regarding "Successors and Assigns."