Property has a assumable first NEED a 2nd and or rehab loan

There is a multi fam thats underpriced for 5.8 mil assumable first of 3.8mil. net income of 500k Reselling as condos the poject is worth 15mil I am looking for a way to cover not only the remaining purchase price but be able to rehab the units. Is this possible and how might I go about it. I am on a first name basis with the banks I work with but from what I have been reading on here It seems that a hard money lender may be a better way to go.