How to fund the 20% for a duplex

[Gabriel Benavidez]

So I bought my second rental about 4 months ago and tenants have been placed and I did put 20% down on it with that being said i been saving up for my next buy and by the looks of it it won't be till 6 months from now when i will be in the position to buy again anyways today my friend of mine is telling me her boss is thinking about selling her duplex and so far i don't know how it looks or for how much it will sell but she said it was built not to long ago and well kept, i do know the neighborhood very well that the duplex is in and i know for a fact it will do good. But the thing is right now I don't have the 20% to put down I believe the duplex will sell about 180k 250k, I wanted to see what other ways I can fund the 20% I also do not want to do an FHA loan or partner up with anyone.