Roberto bought an apartment building for $1 million. In year 1 he spent $50,000 on repairs and received $100,000 in rent. In year 2 he spent $200,000 on improvement and received $150,000 in rent. In year 3, he spent $25,000 on maintenance and received $150,000 in rent. At the end of year 3 he sold for $1.3 million. What was Roberto's IRR?