A bond of nominal amount $100,000$ is to be issued bearing coupons payable quarterly in arrears at a rate of $7\%$ per annum. Capital is to be redeemed at $115$ on a single coupon date between $10$ and $20$ years after the date of issue, inclusive. The date of redemption is at the option of the borrower.

An investor who is liable to income tax at $30\%$ and capital gains tax of $45\%$ wishes to purchase the entire loan at the date of issue. Calculate the price which the investor should pay to ensure a net effective yield of at least $6\%$ per annum.