Did it myself also, really not that big of a deal
I also got the "Flagship marine" unit w/heat and I am happy with it.I think the thing that took me the longest was figuring out the place I wanted to put the unit and where to route the ducting. Measure twice, cut once.Also be aware that when someone else installs this for you they care less about the placement and routing of ducting. I have seen ducting run right through the middle of cabinets, not giving a damn that they made the cabinets next to useless now. And this is all with "Profesional Installers". Just laziness to move the ducting into the corners or out of the way I guess, they just want to get the job done as quickly as possible.I think the hardest (well not really) part was actually cutting a hole in the bottom of my boat for the thru-hull. Strange feeling doing that. I really took my time and even beveled the hole for the and installed a flush mounted thru-hull..I think the next important thing is have a nice sturdy platform for the unit. I built out of wood, 5200'ed it in place and epoxy coated the whole thing. My unit isn't going "anywhere" now.Here is a link to my Install http://www.imagestation.com/album/?id=4289176283