Conforming/FHA/VA. 

If it were me, after a week I would send a certified letter to the sellers POA letting them know you stand ready to close in conformance with the contract.

While I realize that non-conforming loans can choose their own restrictions here, let's talk about what's most common.Under what circumstances do the seasoning rules apply?

You aren't going to get a conforming loan (or probably any loan) with a different set of application of payments rules.

If you are looking for someone to lend you money without having to conform to Fannie/Freddie guidelines, you are looking for people or probably banks and credit unions that loan their own money rather than selling the loan. 

Conventional, conforming loans (Fannie/Freddie) don't come from the banks. 

I use exLandlordforms.com to create my leases and the way it works is the lease it creates conforms to local and state laws.

Explain to the loan officer that the house is non conforming residential and will be used as residential .

I don't mean to America bash, but I think people here are more into conformity and keeping up with the Joneses than being revolutionaries.

If the well services 15 homes or 25 people then it will be considered a public water supply and need to conform to EPA regulations which are terribly restrictive.