Holding costs part of Renovation

[Rick Turman]

So, i'm starting to re-think if I took the right step.  I used the MPP formula to come to a great price on the home, which I may be in escrow by as early as Friday.  Woohoo!  Long story short is, After I look at the MPP formula longer, and my lender only providing 80% with me footing the remaining 20% doesn't leave that much room to breathe. Where I'm going with this is, have any of you fluffed your Reno cost to include Holding costs or, are they paying out of pocket for those?  

Lender Offering:

ARV: 133,900

80% ARV: 107,120

20% ARV: 26,780

Here's my MPP Formula Layout:

MPP: 107,660
Actual Purchase Price: 93,900
Reno Costs: 40,000
Holding Costs: 26,000 @6mo
Selling Costs: 194,000
Potential Proffit: 34,100

AM I overthinking this or am I on the right track?  So in total, I will front the 20% and the Holding costs if any which could equate to a total of ~$52,000.  What do you all think?  Thanks!