You can by the condenser online but it won't come charged because the AA coil is a separate part that sits on the furnace.  

We are building an addition, refacing the exterior with limestone, changing the roofline and installing a metal roof, replacing concrete, new landscape and resurfacing the parking lot. 

Normally the coil is the deal breaker when it comes time to buy a new one.

Another option is to dress up the metal railings with a wood cap that you can stain.

Market rate would be about $1600-$2,000 depending on condition.  2nd floor is old and run down looking, but overall ok.  2nd floor has an enclosed porch that is supported on metal beams but looks like it needs to be totally fixed, peeling paint, torn screens, rotting floor boards. 

In general, these are going to be the extremes ($60 per square through $200 per square).So, if you add materials and labor, you're likely talking between $150 and $300 per square for a licensed/insured contractor who is accustomed to working with investors.Of course, if you want a different type of roof (metal, aluminum, clay, rubber, etc), or if the roof is complex/steep, or if the roof is really high, you'll definitely see variations from that range.

If most houses in that price range have some sort of premium roof (metal, slate, whatever), then I agree the 3 tab shingle will cheapen the house and make it less competitive. 

However, it is a combination roof on a house that had an addition - the original roof is metal shingled, the addition is asphalt shingles.

AC condenser went out in a unit I closed on this month...Property management co submitted bid to do the replacement for $5k in-house (for condenser and evaporator coil to bring up to 410A from R-22).  

They seem to come in two types-metal grate and a mesh that goes overtop of the gutter.Wanted to see if you have any advice or even think they are worth it.Thank you for your advice and input!