Creative ideas needed for financing down payment of an Owner financed deal

[Desiree Sprague]

Hi am a new investor. I purchased my first mobile home in Ohio two years ago and it is going on the rental market in February of next year due to a family member living in it at the moment.  I am also a travel healthcare nurse and currently under contract in Hilton head Island South Carolina.  I am very interested in getting into the short term rental properties here on the island. I am looking at making my first deal on a short term rental property using owner financing.  The asking price for the condo is 349,900. The owner is asking for 20% down to finance and set it up like a 30 year mortgage balloon type payment. At the end of 2 - 3 years The rest would be due in full (hopefully rates will be down in 2 to 3 years).  This would still leave me coming up with 70K for a down payment, which I do not have, so I am looking for a creative loan option for that down payment. Any other suggestions / ideas also would be greatly appreciated.
Thank you in advance.