Killing an old lady is also illegal, but don't worry - if she doesn't have any family that could sue you, it's okay. Nah, that's not how the world works
Murder is a criminal offence, which is entirely different. The police will arrest you for that. This is a civil case where it's up to you to take action.
http://www.diffen.com/difference/Civil_Law_vs_Criminal_Law
You can complain to the FTC and they may take action if they deem it's worthwhile. That is pretty much the only consumer protection you have. If you bought it on a credit card then you could try getting a refund from them.
If you rent a house, yes. If you buy it, no. Once you buy a house, you own it from top to bottom and you can blow it up for all the previous owner cares because it's legally yours.
You don't know what you're talking about. Covenants are real and are legally enforceable.
http://en.wikipedia.org/w/index.php?title=Restrictive_covenant
"In
property law, land-related covenants are called "real covenants" and are a major form of covenant, typically imposing restrictions on how the land may be used (negative covenants) or requiring a certain continuing action (affirmative covenant). "
"These CCRs might, for example, dictate building materials (including roofing materials), prohibit certain varieties of trees, or place restrictions on the number of dwellings that may be built on the property. The purpose of this is to maintain a neighborhood character or prevent improper use of the land. Many covenants of this nature were imposed in the 1920s through the 1940s, before
zoning became widespread. However, many modern developments are also restricted by covenants on property titles; this is often justified as a means of preserving the values of the houses in the area. Covenant restrictions can be removed through court action, although this process is lengthy and often very expensive. In some cases it even involves a
plebiscite of nearby property owners. Although control of such
planning issues is often governed by local planning schemes or other regulatory frameworks rather than through the use of covenants, there are still many covenants imposed, particularly in states that limit the level of control over real property use that may be exercised by local governments."