Repurpose existing buildings: Of course there are parts of the building which cost money to bring up to code, to fix, or to eliminate. But these costs do not compare to the enormous amount you save when you purchase a pre-existing building, as there is a huge creation of value there.
Create smaller units: Not only can can fit more units in a building if they’re smaller, but if you are going to rent to lower-income people, the utilities would have to be cheaper too. Smaller units kill two birds with one stone.
Leverage mass transit/walking: This goes along with the previous tip. If tenants don’t have to pay for parking, gas, or upkeep on a car, this also makes rent easier to come by.
Splurge on windows: Again, this one comes down to utility costs. While new, energy-efficient windows can be a big expense, they will pay off in the long run in the form of lower heating and cooling bills.
Ditch the carpeting: Tile or hardwood floors might not be especially cheap compared to industrial carpet, but they can go many years without needing to be replaced. Furthermore, avoiding carpeting allows for less down-time between tenants.