$28.$ Allison Versace forms a corporation to hold an apartment building. The building has a basis of $$200,000$ and a fair market value of $$1,200,000.$ Shortly before transferring the building to a corporation in exchange for $100\%$ of its stock, Allison takes out a mortgage of $$500,000$ and the corporation assumes the debt on the incorporation. What is the amount of gain to be recognized by Allison?