[Tishabet]

Let me start off by apologizing for what is sure to be a long post!

OK guys, I'm looking for advice on what to do with my roof as well as how I should go about doing it. Here's the deal:

My wife and I have been in our condo for about four years now, and one of the coolest features of the place is the roof access. We own the top floor of our building and have a spiral staircase up to the roof along with exclusive rights and access. In the more temperate months, we are up there 2-3 times per week and often grill and eat dinner there, and I'll often head up for a late night cigar and stargazing as well. When we have guests or parties people love spending time up there.

Currently the roof is just... a roof. The roof surface is a type you can walk around on (I believe it's "modified bitumen" based on some brief research) and isn't so bad, though it does get very hot and will make the bottoms of your feet impressively dirty. The entire roof has a slight pitch dropping to a single drain on the inside wall. Total surface is roughly 1200 s.f.

We've decided that it's time to take the plunge and spruce things up on the roof, both for our enjoyment and for future resale, although the latter concern is more of a "let's not lose money" type of concern than a "let's make a profit" type. The most obvious thing to do is to build a roof deck covering at least some of the roof, and maybe some low wattage lighting (currently there is no lighting up there, though we do have power). Although I have wrenching skills and have helped build a "traditional" deck, I think this project is going to be performed by a pro. That being said, I still have a bunch of questions and concerns, and I figured the Pelican brain trust could help!

Roof deck engineering
At face value building a roof deck like this one should be dead easy... a rectangular one-level deck. However, there are a multitude of potential problems swirling in my head... how to frame/support something like this? Is the roof able to support the load, and how do I find out? Is it OK to have load resting on a roof surface? If not, is there some way to support the deck entirely from the external brick walls? How can I ensure reasonable access to the roof itself for future maintenance and repair?

Roof surface
The roof is five years old, but is already creating some "bubbles" that are like a pillow of air (see pics) as well as crazing. Should I do something to the roof before covering it with the deck e.g. apply elastomeric surface? Is the existing roof surface material suitable to either be under the deck or potentially supporting some sort of footings?

Contractors
I've never dealt with a contractor before in my life... I've read up a bit on the "gotchas" regarding insurance and the bidding process, but that's about it. Should I try to find one contractor to do the whole shebang, or a roofer to prepare and weatherproof footings and a general contractor to build the deck or...?

Bang for buck
The wife and I have saved up about a decent 911SC worth of funds. Where do you guys think we should concentrate our spend?