I was outside installing gutter screens and noticed a torn window screen and a slightly open window in the common area.

In a rental case I'm guessing most people would not be interested in those circumstances,  and those who would consider the option certainly wouldn't pay a premium for it.So I guess the question is,  when accounting for water, sewer, and electrical hookups,  THEN what time to install and what is the ROI?   

Ultimately as the property owner you will be held responsible, with little to no recourse, should the local jurisdiction step in or if unsafe installations fail or cause injuries. 

It may be cheaper to just lay that out over the pad, and given that it doesn't require watering, it may be an attractive option for a potential buyer - plus they can always remove it at a later date...You can get most types of turf for around $3 a square foot, which will be cheaper than removing concrete and installing turf (and likely some type of irrigation system).

I kept the radiators and installed window AC units.

Running the circuits to the main panel may require installing a larger main panel.  

I just read another topic about finding good contractors and being wary of people asking for money up front.I'm about to order around 30-40 ft of granite countertop with install and the guy says he will need a 50% deposit with a quoted price of around 2k.I just wanted to know if it's normal for them to ask for such a large deposit before they begin work (e.g. getting the slab for fabrication etc..)

It is easy and quick to install AND maintain.

If you are not familiar with programming in HTML, then a blog would probably be your best bet as they are easy to install and use.In addition, search engines and spiders love blogs because they are a prime source for fresh content.

It not that common that apartments report this info to the credit reporting agencies as they are more setup for installment loans and revolving credit.