Bear in mind that online reviews usually number a handful, so it's hard to determine quality based on reviews. Faucetdirect.com has lots of rods. Brass rods are the most expensive. I bought stainless steel. The Kohler rods would have been my first choice, but my shower is 58", and theirs and many others start at 60". I had to buy Moen and it does look nice. We have good ventilation so I don't think rust will be a problem. Location: Once you have the rod and shower curtain, you'll figure it out pretty quickly. Most shower curtains are 70-72" long. Leaking: Curved rods won't prevent it. I bought a shower curtain liner at BB&B that has suction cups along the sides. Shower curtains: JC Penney, Macy's, Kohl's, BB&B, Pottery Barn, Croscill.com, Overstock.com, etc. I've looked at hundreds and haven't found what I'm looking for. Most look pretty chintzy imo.

My $.02, I don't think you need to hang those window treatments at the same height. I woudln't. I agree with PP in saying that since the ceiling heights vary, I would treat each window individually re: height. As for rods, I hear you on the cost! In my old living room, and now my family room, I put my curtains on a traverse rod. Not the prettiest but the functionality was key. They now sell decorative traverse rods. Much cheaper option than your decorator's option. Alternatively, I have used the adjustable rods from Country Curtains that are metal but the finials are wood (Regal line). I was pleased with them and they are a great price. If you have the curtains on rings, they would be easier to open. I didn't use rings and it was a little bit of a pain to open and shut but I did it several times a day in my son's room due to naps and I survived. So, I really just depends on ease of use, decor, etc. While $750 is a lot of money, it is pretty much the going rate when you do these things through a decorator. For me, I remedied that by going high end in some rooms and budget in others. Hope this helps a bit!

Usually there is the main front rod and then the back rod has a hook on each end that lays over the bracket that is holding the main rod. I have seen them separate and I have seen what Kippy said.

Very pretty porch and yard! Any 12' curtain rod will need supports, but your best bet is a solid metal. Check with the manufacturer--they will usually recommend how many supports for their rods. That being said, why do you need a curtain at all? Afternoon sun? If so, maybe a shade would work better.