"Buying" parents house...best strategy

[Jason Munger]

My parents (both still living) have a home that they no longer live in and are looking to sell it.  They have moved south so it is vacant - if that impacts your suggestions.

They own it out right, so there is no mortgage. 

I'm an only child...so weather my parents "sell" me the house for a dollar, I one day inherit it, or the money they get from selling it...will come to me. 

I want to buy the house from them and turn it into a rental property

A) Do I buy it from them at market value?

B) Do they "give it" to me...and how would that impact taxes and financial gains?  Seems like if I buy it for $1 I would pay a HUGE capital gain when I sell it, right? 

*I would "owner finance" if I bought it from them at market value.

They are trying to get out from under the negative cash flow of a house that is just sitting there.  I'm looking to pick up a income stream.

Thanks!