For this, I have to compare my condition or projected condition to competing rentals, how long an improvement will last, (Granite counter-tops versus an upgraded toilet paper holder) the trends in the market place, such as what tenants appear to be trending toward liking, how popular a particular item is, and wether I might get only the same rent as I would have, but possibly just get a better tenant.Those are all bottom-line, figuring out the net dollars concerns.2) How much time and aggravation it saves me:Here, I go beyond just how many net dollars in extra rent I'll collect, versus the cost of improving, and I consider how much extra time it takes me to wait another week to rent it, or possibly how much time I waste dealing with a "b" quality tenant, when for an extra $1,000 worth of upgrades, I might have attracted an "a."

I'm currently redoing an apartment that I've owned for a long time, the last tenant was there for 21 years, with new granite countertop, new kitchen cabinets, all new flooring, new ceilings, and a new deck.

When i'll say lower end I mean using the cheaper laminate flooring, cheaper cabinets, cheaper countertops etc.

In this area you can buy houses for under 10k.I am thinking of just always doing the same thing to these houses.1. white kitchen cabinets, with laminate counter tops with the 4 inch back splash.

My personal preference is that 1 nice cabinet with 1 seamless counter top looks better than 2 cabinets put together.If you have an Ikea store near you, they sell some double sinks at reasonable price!

Minor roof repairs are getting done, the exterior has been painted, the kitchen cabinets and granite countertops are on.  

(this was my estimate with input from the realtor who apparently does demo on the side)- All new flooring (combination of carpet, laminate, vinyl)- All new interior doors and hardware (6 panel hollow)- New (matching) light fixtures- Most or all new interior trim- New counter tops with modification to remove partial wall and add breakfast bar to open space between kitchen and dining room- Refinish existing cabinets- New bathroom fixtures (vanity, sink, toilet, tub) in both bathrooms- Likely sub-floor repair due to the significant amount of pet damageThe major areas that I didn't look closely at (because of the pile of junk in the way) but would certainly need to if I was considering this include the mechanicals (AC compressor appeared original), septic system, well, a closer look at the roof, and a closer look at the deck. 

High(er) end laminate flooring, granite counter tops, porceline/ceramic tile in bathroom.  

I even threw in some premium things not found in any comps (LED can lights and quartz counter tops; they didn't cost me any more than normal stuff would and they look great).

They are a consignment store so you will pay a 10-15% markup and then tax but they have cabinets in stock and they are half or less then what I see at Home Depot.They also have granite countertops in 8 or 10 foot lengths (I forget the exact)  these are precut with an edge finish on them.