anything you add (new handrail, lighting) needs to meet new code.with safety issues like the basement stair treads, you might keep the basement off-limits (move laundry to main floor maybe).before renting, check with your city/county for rules for rentals - they may require smoke detectors installed (one in each bedroom near door, one outside each sleeping area, one on each floor level).FYI, during a remodel, if you install/update your Mechanical, Electrical or Plumbing systems, you may need to update that system in the whole house.

Not to mention if it's a septic system, then you need to make sure the septic tank is rated for how many bedrooms you are making the thing.Structure - Depending on the style, a new stair case may be required, which may require installing a few supporting beams where the stairs go through the upper or lower floors.Fire stops - you will, depending on local codes, be required to have a fire stop between each unit, such as a 1-hr burn rated wall.  5/8" drywall between each unit. 

So we had existing stairs off our kitchen and just built a mudroom to add privacy for access through the back door.

He will review all the work done and look for other problems, railings, stair treads, cement work, etc.

Call neil or whoever can give u a lead free cert. assume all old windows/trim/doors go, as well as old stair railings treads before calling, but have him zap your place and tell you everything that must go, you might be able to keep some stuff. 2.

This is a $1250/month rental.I am thinking about carpeting the two upstairs bedrooms and stairs and putting wood pergo in the upstairs hallway.

The numbers and the seller's motivation are all that matter.FWIW, though, I will not let my buyers cement a deal based only on the seller's repair estimates, as that is part of the buyer's due diligence.

-Plumbing/electrical = 5k-Kitchen and bathroom = 15k-windows = 6k-Flooring = 8k-painting = 3kSo, could I get the drywall, siding, porch/stairs and permits done for 20k?

This one especially is a PITA being a 4th fl walkup in the multi where I live, I don't want to sit there twiddling thumbs nor run up and down the stairs 18 times!

Starting with the stair-step method is a great starting point, but fine tuning the bid based on your ROI calculator is needed to finalize.