Some friends of mine back in IN did what you're suggesting and love it. They had their concrete entryway done over with the overlay to look like brick and it's incredible. We have an old concrete patio that we're going to redo (one of these years) in the overlay, using a stone finish. We thought about putting a layer of decking on but the look doesn't match our yard and it's too thick. The overlay is not very thick -- I don't remember specs but I can't imagine it would be much thicker than flagstone. We only have a few inches clearance between our current patio and the door sill and that's plenty of room for the new surface. I've seen samples of the product and it looks incredible, and care is supposed to be a dream. I'd be interested to hear if anyone has any bad experiences with this. See link for photos but I can assure you the finished product looks much better than the photos can show. In case you can't tell, I'm hooked on this idea :) Here is a link that might be useful: concrete overlay

The "Forever" stamps are calculated for 1 oz. first class letter mailing. If I'm mailing a package or an oversized envelope, etc., requiring more than 44 cents, I just let the postal person use their postage meter labels. I've futzed around with 1 and 2 cent stamps to make up for postage increases long enough - these Forevers are brilliant as far as I'm concerned. I bought $100 worth when they were first introduced at 42 cents way back in April of 2007. Still using them with a handful of cards left to go. I'm glad there will be commemoratives though, the regular postal issues can be a bit bland.

Stamped concreted is finished with a special tool, a stamping tool that looks kinda like a jitterbug. This is done before the concrete is dry. Engraved concrete is done after the concrete is hard, like cut is a saw. Al

Stamped concrete can only work on newly poured concrete. When the concrete is "green", close to cure, the powder color is added and then stamped on the fresh concrete to create an impression. Personally, I'm not crazy about it as to me it looks to fake. Your best bet to save money, is to paint the surface with a deck coating. Kelly Technical coatings has a line of deck coatings that have a variety of color choices. It's easy to apply and is water based. This will spruce up your patio nicely for an inexpensive cost. We did this for a customer a few years ago. It came out nice and it was inexpensive. You may have to re-coat every 2-3 years. It's lot cheaper than a new pour. Plus the cost to remove the existing, yard repair, etc... For the new section, you could integrate the natural stone as a border. As long as your new pour is separate from the old, you will not have any cracking. Even a 1/2" break is sufficient.