Confusing between Cash on Cash return while doing BRRRR calc.

[Karan More]

Hey Guys,
I am trying to calculate Cash on cash return when a BRRRR is done. Here are my inputs:
Purchase price is 102K (19.6K down pymt, 78.4K mortgage and 4K closing)

Rent is $1,500.

Rehab cost $15K

Expenses are coming to be $1,052 /Mo which includes (Mortgage + Tax + Ins + Vacancy + Prop mgnt + Capex). Leaving Utilities and outdoor maintenance to tenant.
Cash Flow is $488/Mo.

Therefore CoC is coming around Annual cash flow/(Down payment + Rehab + Annual Expenses) = 5376/47224= 11.38%

Is that correct or am I missing something here?

Also, If I plan to Refinance it for ARV 155K. How does my Cash on Cash calculation comes up after ARV into picture?

Any guidance or help is appreciated.