With your Fico and down payment, all you need to do is make sure you pass the debt to income requirements. 

Apply for a dimensional variance on the vacant lot to allow a smaller lot and/or setback so it can be built upon.Your best first steps are to sketch a plan, possibly with an engineer's help, then contact the zoning department to discuss your idea with them to get informal feedback on your liklihood of success before you spend a lot of money.

It would be a tight budget but I do have money set aside for repairs.

Most of the properties we acquire are with little to no money down (even $0 down!)

What if you need to inject more money? 

Jonathan, The tenant does not currently owe any money.

Hard money loan How did you add value to the deal?

Even if rents are trending up, if your tenant base can't make ends meet, the asset won't perform.

money dont care

Depending on how much money you're willing to pay, it might make more financial sense to use another platform.