How do I calculate a cash-out refi after a hard money loan?

[Jobee Vincent Buenaventura]

Hey everyone,

I'm not sure if I'm just having brain fart or something right now but how can I make sure that when I use a cash-out refi to exit a hard money loan, I'll have enough equity in the property to get back my money and then some? 

Let's say the acquisition cost was $300,000, rehab cost is $125,000 and the property is projected to appraise for $600,000. So that's basically a $425,000 loan give or take some points/fees. Then once the rehab is done in about 6 months of financing $3,500 a month (totaling $21,000), the property appraises for $600,000 and I take the steps to do a cash-out refinance for 75% LTV which is $450,000. My loan balance with the hard money lender is probably around $400,000 at this point so will I be getting the difference of about $50,000 less closing costs/fees?

Thanks!