I did hickory hardwood floors, new countertops, new stainless steel appliances, Oak furniture (still bought at yardsales), very nice bed spreads, walk in shower with nice tiling, etc. 

Assuming you can build 3 stories with no setback on the third floor (if you're a corner property, if either adjacent house is 3 full stories, or if either lot alongside yours is vacant) you can go 3 stories.

Paint, flooring, kitchen, bathroom. 

A proof of funds letters shows that you are ready to buy a property, not just there to take in the floor plan.

Replaced flooring in living room and master bedroom.

If all the rentals have laminate, don't do hardwood floors and granite counters.

It’s a 3 story, 3 family, 3k sqft, 1908 Victorian, 2 bedrooms each, 7 miles from NYC, and rental comps reflect about $2300 a piece if rehabbed (top unit/floor was updated about 8 years ago). 

Flooring, paint, lighting, HVAC updates, plumbing updates, new kitchen cabinets and appliances.

Did new flooring at the time as well as replaced Sheetrock with drywall, new pipes, kitchen, double pane windows, and HVAC system.Plus 5-6 years ago put a new roof.Based on 3 comps I pulled the ARV of his house is $553k. propstream says valued at $581k.

@Robert ArquillaJust some more info: The main reason for the post is about possibly turning the bonus room on the second floor into a bedroom and adding a bathroom to change the house from a 2/1 to a 3/2.