The first 2 with one you do not have your property under contract yet and the other the property is under contract but your buyer can still back out of the deal and doesn't have a bunch of non-refundable money they could lose (skin in the game).

Pedro,I am not sure what you mean by not having a lot of money, but as a first time investor you will mostly likely need skin in the game. 

Then, assuming you have a contractual arrangement with your buyer, just represent him/her as fiduciary and the seller as Customer, in a normal brokerage transaction.The other option is to just put the property under contract, then assign the contract, but again, this needs to be fully discussed in advance with her broker, then fully disclosed to the seller, so they can't come back later and sue you for making "too much" on your transaction fee.I strongly suspect that your sister will be required by her broker to use standard contracts and forms made available by your state's real estate commission. 

You'll likely be responsible for "normal" home inspection repairs rather than an entire tenant turnover.

I know the normal BP responses of Brrrr'ing and other forms of lending - but this is the particular route I'm interested in hearing stories on if you have 'em! 

The additional $2,000 in cash invested were normal wear and tear over the years and the addition of a deck.

NO, your equity is your skin on the game. 2.

I replace the built in microwaves when they break, but do not provide them on a normal basis.

I wanted skin in the world of real estate other than my current home.

These would not be just normal 1031 exchanges.