It depends on the size of your deposit. Can you be more specific.

One can calculate the cost of a second mortgage by going to the website 'MortgageCalculator'. Here one can find information about achieving a second mortgage and use the calculator to calculate the cost of a second mortgage.

That depends on the cost of the property and the interest rate of the mortgage. There are websites with mortgage calculators.

When in a no cost refinancing situation the person who has the mortgage actually pays for them however they are built into the financing or mortgage itself.

There are always costs involved when one decides to refinance a mortgage although marketing schemes may disguised refinancing as "no out-of-pocket cost refinancing." The most frequently used "no-cost" refinancing is simply to add all the cost to the existing mortgage loan balance and increasing the amount of mortgage to cover for everything.