If you don’t use a professional and things go wrong they will go very wrong really fast and it will cost you ten of thousands of dollars if not much more.

Not much has change since 2007.

Me and my wife have changed our minds on the home as it's a little far out of town, and the value has risen a considerable amount.My question is, if we manage to sell the home in the first few weeks when we buy it, how easy is it to sell it from a documentation/legal standpoint?

Time has a way of changing people's circumstances and needs.

I believe in June Fannie/Freddie changed the 10% ownership to 20%.  

I've run into deals where things keep changing and I usually bail. 400K is a sizable purchase and it seems that neither you or the seller are completely ready to make this happen smoothly in a short period of time.

I know we have no right to change the terms of the lease (esp rent) until it expires. 

You have to be ultra careful because with this length of time holding the property a lot of things can go wrong and the market can change temporarily for the worst due to weather, holidays spike in interest rates, sudden oversupply etc...

I had hot water tanks changed.

Also, most window companies change their designs and stop making replacement parts on a regular basis.