Bob, I am now doing my own install for a new wood stove and I went through the same thought process as you are now considering. The decision comes down to seven questions: 1) Do you have the tools, knowledge and time to do it yourself? (apparently you do); 2) Do you have the money to have someone else do it?; 3) Will this someone else make a conscientious effort to do it right? Have you seen other work he/she has done?; 4) Will the installer follow all the manufacturers' instructions?; 5) Do you trust the installer?; 6) Does the price include delivering and setting up the stove, supplying, delivering and installing the hearth, placing the stove on the hearth, supplying delivering and installing the ceiling suppost box, properly trimming the ceiling around the support box, supplying, delivering and installing the class A chimney, double wall stove pipe, and other accessories recommended by the various manufacturers?
I finally decided to do the install myself with a friend helping. We have already installed the ceiling support box and I am now laying out the hearth. The stove and hearth have been carefully measured and designed to exceed all code requirements and be large enough to hold a rack of stove tools, an ash pan, and a cradle of wood. This morning I will finish a sheetrock patch job. This afternoon I will start the framing for the elevated hearth with Outside Air Kit entering under the hearth. I have already designed, and next week will build the "kit" to install a chase around the chimney where it exits through the ridge of my roof.
I have hired a local reputable roofer to cut the hole in the roof and install my chase kit aroung the chimney. I will supply a bundle of matching shingles, cap/ridge shingles, siding for the chase, and flashing to match the green roof. He will do all that work. Once the chase is finished I will order a chase cap and install the chimney, chase cap, storm collar and chimney top. Then I will break-in the stove with three progressively increasing fires. I'll be ready for next fall.
I built my own house 4 years ago and hired some very reputable guys to do most of the work. We butted heads through most of the project. I wanted them to install LVL's, siding , roofing, insulation, sheathing, sheetrock, rim joists, TJI's, etc., according to manufacturer's recommendations. They did not think the manufacturer's instructions were very important because"We have been building houses for more than 30 years and we have never had a house fall down...", etc. I won't get into all the frustrations!
I would recommend you read and learn as much as you can so you truly understand beforehand what and why things are done a certain way. Then do the job yourself with a helping friend and use a reputable roofer to do that work if you feel squeemish about it.
You will probably do a better job than a stranger would, will save some money, and have the satisfaction of knowing the job is done exactly as YOU want it.
Good luck,
John