拷贝一下柠檬link里的IRS 定义的房地产活动:
Real property trades or businesses. A real property trade or business is a trade or business that does any of the following with real property.
1. Develops or redevelops it.
2. Constructs or reconstructs it.
3. Acquires it.
4. Converts it.
5. Rents or leases it.
6. Operates or manages it.
7. Brokers it.
问题： 1.买房子， 看房子，找贷款，closing算吗？
2. 和租户打电话，叫修理，催房租，发信件，存支票，整理账目， 算吗？
3. 还有什么补充？
4. 自己管理，一般多少个房子可以算Real Estate Professional？ 大家应该花的时间都差不多。