There has to be a way to draft language that makes it undesirable for the tenant to want to sublease a space.

Examples include office space, machinery and equipment, vehicles, computers and peripherals, and real estate.Besides renting the assets personally, you may use a multiple entity arrangement such as partnerships, S corporations or limited-liability-companies to rent the assets to a corporation.

I've tried to sell these lots for $1000 over the past year and been told due to their location/slope, they are undesirable/worthless.

Redwood City has parts that are undesirable.

Here in CA, the challenges to development from a regulatory perspective make development undesirable for business people who take risks in exchange for profit. 

I will hate for you to place your private funds into undesirable areas, confusing condos, rusty mobile homes or go with an unscrupulous "partner".   

So, at least in my market, sellers that offer seller financing only do so because the property has major issues keeping it from being financed in the first place, or they are can't get any other offers for whatever reason (undesirable area, etc).There's a lot of talk on BP claiming seller financing is a great way to get into investing. 

In that case, it may take longer to rent your unit or you will have to accept undesirable tenants because all the good ones can go get a nicer property next door.Pretend you are a tenant seeking a place to live and compare your property to the others.   

There could not be a clearer link between a liberal Supreme Court justice's line of thinking and eugenics than if she said, "we need to legislate means to abort undesirable portions of the populace since legally we can't sterilize them anymore".

Or they want to keep "undesirable" renters out of town?