Review their management agreement.

A single member LLC can be cheap to set up - a few hundred bucks between state registrations and a legal zoom operating agreement. 

Hi all,I have used BigggerPockets lease agreement forms last year.

Anyone please have any advice or example/blank purchase contracts and assignment agreement forms I could modify?

I recommend your purchase agreement include an opportunity to review any lease agreement, payment history, and application screening for current occupants.

Their management agreement is win-lose arrangement. 

Then you will have a 10ish min quick walk through the property and if his pictures matches the reality and you don't see anything abnormal, then after you sign with him assignment agreement and you put nonrefundable deposit and close in about whatever days you agreed on(usually up to 10).  

Bottom line is you can rent out on a short term basis and you don't get into a legally binding agreement during the first year where you lose the ability to occupy the property when you so choose.2. 

We negotiated favorable terms with the seller, ensuring a beneficial agreement.

Put together an agreement between you and your parents, and with an agreed price, you can buy them out once the home has been fixed up and refinanced.