Too many people are over extended and justifying this attitude.What is being ignored?

I told them that I fully expect them to cover rent for any extended period of time that the house is not rented out.

I therefore assume expenses will be 50% of income for older properties and 45% on the newer ones - based on what I've read on these forums this is where it ends up over extended periods and my strategy is to hold for a long time.

Just last month my client wanted to extend a bid that I felt could push us too close to his final rehab budget.

Perhaps he would be willing to extend your term by graduating the interest rate after 5 years, thus increasing his payment (gotta be careful that this will not be too detrimental to your cashflow).

I listen to the podcasts whenever I have an extended drive.

If you pass your deadlines and its a hot market the seller may refuse to extend, keep your EM (though I hear that's hard in CA) and find a new buyer.

How do you suggest dating the purchase agreement so that it will remain valid for the duration of the lease term?

How long of  a duration is   recommended to wait before sending mail and doing your  next wave of  marketing i.e second or third round of letters?

You are the one taking the risk of extended vacancy not them.