How to combine the loans?

[Taras Kokhman]

Hey everyone! I came across a valuable deal in Miami, FL. Its is 4 unit building that is 85% vacant and need some minor renovation. 

The seller accepted our offer of 550k and willing to finance 250 for 5 years. We are looking to finance other 250k to make a purchase. The end goal is to fix up the property, increase value and refinance within 1 years and hold it.
What are the beat ways to finance remaining 300k ? Can the hard money lenders help? Thank you.