We're adding a master bedroom, enclosing a patio and adding a mother in law suite.We obviously want to keep costs low and I feel a bit ignorant about the process.  

How about using a bicycle for transportation, building your own home using stone from your land ala Joe Dominguez and Vicki Robin, "Your Money or Your Life".

If the bad area is convenient to expressways, public transportation, and vital services and adjoins a much nicer area, the prospects for improvement sooner rather than later are much better.

I'm seeing homes $1500-$1600 month for a 4BR 2BA 1yr lease, one bathroom in horrible shape, never is painted, AC units broken and not fixed, and one of the bedrooms is actually a former dining room connected to a living room, just enclosed with a big piece of drywall, no priming/sanding necessary.

Get their numbers and substitute them with REAL numbers and add in all the expenses they left out (management, maintenance, cleaning, adverts, transportation cost, etc) and build your offer that way.

Great schools close by, low crime, residential tree lined block with easy access to transportation as well.

I'm not familiar with Carlsbad's specifics, but thise numbers don't take into account Big (note the capital B) costs for water and sewer capacity, school, transportation, permitting, and a bevy of other costs.  

In much less than 30 years our transportation system will be completely overhauled simply by technological advances. 

It become worth a lot when it gains (1) rarity (2) utility for another owner due to its attributes-size-access to transportation routes-access to markets, or (3) when it is sub-divided and has infrastructure added to it.If your land doesn't meet one of those three attributes you should take a very hard look at WHY you're buying it.all cash

.- The public transportation starts to get crowded.- If the trend continues...... it becomes a viable, maturing neighborhood, as some of the Artists/Musicians/Yuppies begin to have children.