@Bill Brandt They do but the estimate is not very reasonable.

Again just estimates from any with experience having done extensive multifamily rehabs would really be appreciated in order to see if my numbers are within the ballpark of making this work. 

A site such as Zillow can only use an algorithm to come up with a rough estimate.

I went ahead and estimated my taxes based on my assumption, paid more taxes, and filed an extension. 

Also when on the phone with a seller, how do you quickly come up with an estimate for their property- I know you definitely don't want to tell them you'll give them a callback, you want to give them something to think on while you come back with the Maximum Allowable Offer. 

Also when on the phone with a seller, how do you quickly come up with an estimate for their property- I know you definitely don't want to tell them you'll give them a callback, you want to give them something to think on while you come back with the Maximum Allowable Offer.

I'd overlay without an exigent circumstance, don't think the estimated life is different enough to justify higher cost.

Our original construction contract had an estimated finish date with the majority of work being completed by 12/31/20.

After I rent the whole house out, my property manager estimates about $2400 in rent (conservative).

I'd recommend getting your numbers estimated the best you can and then present them here on BP and find lenders that way too.