I wouldn't sell all, but taking a portion to diversify would be advisable.

What happens if: the rehab costs more than expected, the flip is delayed or the sales price is lower than expected?

The most useful information from either site is going to be past sales.

Once my client is completely ready to submit, I send over a full package to the other party including an the signed Purchase and Sale agreement, a copy of their pre-approval letter or proof of funds, a picture of the escrow deposit, a sheet explaining all of the comps that verify the offer price, and a brief explanation in the email as to what some of the terms are. 

My brother in law and I have been trying to purchase a rental for a few months now but we have been having trouble getting bids accepted.A few days ago we put in a bid on a short sale house last Friday.  

I usually create both a rental ad and a sale ad, both advertising the home as a lease option type of deal, in zillow rental manager (used to be postlets), which then syndicates to zillow, trulia, hotpads, aol, etc.

Regular price is $497.00, but sale price is $47.00.

For the duration of the lease-option the property stays in the sellers name, so it should not trigger a "due on sale" for the mortgage, until the option is exercised. 

A 1031 exchange would be used to sell an existing property you own and buy one (or more) replacement properties without paying the capital gains tax on your sale.  

New investor question here:I have found a short sale that, after running the numbers, appears to be a good deal.