But I always insist on a tour.

You can simply insist that you need a mailing address to send his check and that you can not meet him in person.

The seller insisted I let her stay saying she always paid on time etc, so I agreed.

The tenant still insists on a mold infestation since I will not provide her the entire report.

In my market, if an investor is looking buy and hold, I know I can find properties on the MLS and I insist upon an exclusive buyer agency.  

In some cases, a landlord may insist on a ground lease (for reasons like avoiding a taxable gain on sale or maintaining control of the land and the use of the property).

As in I wouldn't even give you the option but might throw out an unreasonable price if you insisted

—Starting with interests —Exploring options—Insisting on legitimate criteria Negotiating both for good results and for lasting relationships.

I asked her again and again and she insisted that there would be no seasoning.  

Obviously the least amount down and no interest would be best but when the seller insists on interest collection and a down payment what has been your experience in this scenario , thank you