rehab estimation before putting in an offer

[Gil Segev]

Hi all, I am trying to understand the order of actions in the offer process better. Tried asking this in another thread but I guess it got missed. 

Generally you put in multiple offers and only few would get accepted. You can't really have a contractor provide bids for every offer you make or this would be their full time job.

Do you then send in the contractor only for accepted offers? If so, how do you estimate the rehab cost when you put the offer in? Is this just based on experience and a high level estimation?