It boasts top-rated schools and has been adding jobs at one of the fastest clips in the country.General Motors Co. kick-started the town’s growth in 1990 when it opened a vast plant for its now-defunct Saturn brand.

But SF is very resilient economically but I am not sure how other cities in the mid west  or East coast may pan out. 

I would hire a professional, German cocktail roaches are very resilient and can hide and lay eggs in places you never thought they could hide.  

Plant some grass and go get a good tenant.

Just planting a seed, there are various ways and I don't want to mess around.  

So if the carpet is in good shape, I am not sure that I would replace it.There are some things you can do with additional insulation between the floors and additional sheet rock, as well as some sound isolation measures (green glue, resilient channels, etc), but those would require a decent amount of money and messy work in the downstairs unit.  

There are costs associated with building more resilient structures and unfortunately this could be part of the reason some structures haven't been built as well as they could be. 

If you have a hardwood floor it could be the floor itself or the subfloor and hardwood floor rubbing against each other due to a breakdown or missing underlayment.If you have a sleeper flooring system you will have 2x2-4 sandwiched between two layers of subflooring and should be running 12" on center.If you do decide to do the drywall method here is a link to resilient channel http://www.soundproofingcompany.com/soundproofing1...If you do decide to use this make sure that when you hang the drywall that the screws are not too long so that they don't go beyond the channel into the joist or other wise you will defeat your purpose. also when installing the channel you should install it perpendicular to the joist and don't forget to box around any fixture with the channeling so you can properly attach the drywall to it.

My day job is in a field where traditional big data solutions (Hadoop on computer clusters) isn't even efficient enough, which has put the focus on resilient data structures (RDD's) and Apache Spark as a foundation for alternative solutions.

yogurt plant expanding there- among others I can't think of right now...