As to question #1 - if you only had one mortgage on the house, and that mortgage lender/servicer (in this case 'Chase' that you mention) has not applied for a deficiency judgment within the 6 month period after the trustee sale, then No, they are prohibited under Nevada law from suing you to collect the deficiency.
For question 2 - if they send you a 1099, you may not be required to pay taxes if the home qualifies as a 'principal residence'. The Mortgage Forgiveness Debt Relief Act of 2007 uses the IRS's standard qualification for 'principal residence' that was already in the IRS code that dealt with excluding from taxation gains from sales of a person's 'qualified principal residence.'
If you lived in the home as your principal residence for more than two years total time during the past 5 years, then it would more than likely be deemed your principal residence and should qualify for the non-taxable exemption as principal residence on Form 982. i.e. determine the number of full months you lived in the house, and it if is at or more than 2 years, you should be fine.
Of course, I am not a tax professional, so you cannot depend on this answer and should consult with a tax professional/EA/Tax Attorney/IRS before making any decisions regarding what you choose to include on your tax return.
William Devine, II
Las Vegas & Henderson Nevada Bankruptcy & Debtor's Rights Attorney