Question about purchasing, while not using a relator

[Fred Shandler]

(whether it be via bird dog, wholeseller, FSBO)

After you've located and viewed a property, is a letter of intent the next step?

If the initial offer is not accepted, is one new letter of intent needed for every subsequent offer made?

Is acceptance of the offer followed by a purchase contract?

How long does a seller usually take to accept or counter?

How long after they accept do you send a purchase contract (if, that is even the next step)?

Thanks!
Fred