How do you estimate the cost of a rehab?

Next time research how to do it, estimate the time for someone without experience and with experience. 

I want to use this line of credit to fund the 20% down and Rehab of a property. the line of credit is estimated $418Kexample: multi-family house costs $700,000.0020% down payment is  $140,000.00Rehab where possible, paint, new rugs, maybe new appliances to update the experience for the tenants. $10K -$15KMortgage loan estimate amount is $560,000.00-at some point I will need to get an updated appraisal of the property with the update value -After Appraisal assuming the updates improve the value of the property, I would refinance to a new loan.the new loan amount would need to be at Least $700,000.00 to cover the original loan amount and to allow me to repay my line of credit.is that correct?

Not to mention I missed paying estimateds.

Property has consistently been full--Appreciation has been great as well--present market value estimate around $475,000.

When I bought it, the returns were looking nice at a $1,100 per month rent estimate but it's nice that when construction was completed the market rent was $1,275 per month so that was an extra bonus of $175 per month per unit (or $700 per month total) over my initial cash flow projections when I signed the contract to buy the properties.

I estimate the ARV at about $320,000, which was about $72,000 in equity capture.

It is a 5bed 2ba home.Originally, I planned to use the BRRR method to refinance the home for my estimated ARV of 110k and pull the cash out to fund the next property.

It has forced air heat, but no AC with my estimated cost of $5k  Paint, fixtures, etc throughout $5k. 

- What would be good estimate for this rehab?