The apartment complexes I have dealt with will take a scanned copy of the application form with signatures as proof of consent.

I spoke with 5 different attorneys, all of which stated the samething: in NH the lease is viewed as a contract between consent adults and those terms are considered first.

Also that the seller consents to being named co-insured, additionally insured,5) the buyer would pay the property tax every year6) the buyer would pay principle and interest equal to XXX, due on the 1st of each month, directly to the lender or through a loan servicing company.

I'm sure Dion is mentioning aspects of unique situations where you might have a smallish bank or lender, having a cash flush pocket, good credit and good reputation of a buyer, I've pulled some out of the fire here, but with the bank's consent and very early in the default and process.

"Purchaser further agrees that it will not enter into any contract for deed or lease with option to purchase agreements regarding the Property, unless Purchaser is a non-profit organization or has obtained Fannie Mae’s prior written consent."

If all or any part of the Property or any interest in it is sold or transferred (or if a beneficial interest in Borrower is sold or transferred and Borrower is not a natural person) without Lender's prior written consent, Lender may, at its option, require immediate payment in full of all sums secured by this Security Instrument.

No animals shall be kept on the Premises without the express prior consent of the Landlord.Landlord reserves the right to require an additional sum to be deposited with the Landlord as security for any harm or damage occasioned by housing such pets upon the Premises.

The senior consenting to the sale could change that outcome but they would be a fool to consent considering not consenting, preserves their claims against the property.  

Business entity - probably LLC - with a well written operating agreement that governs each parties' rights and obligations, management authority, spells out how money is spent and distributed, dictates how decisions are made and what type of consent is necessary for different types of decisions, includes buy-sell provisions in the event of a dispute, death, divorce or disability, etc. etc. etc. if you decide to own it individually as tenants in common, you need a property management and ownership agreement that addresses similar issues outlined above.

A person who receives a mortgage or deed of trust on real property as security for an obligation payable on an installment or deferred payment basis and arising out of materials furnished or services rendered in the improvement of that real property or any lien created without the consent of the owner of the real property.