Please dont buy that thing. Read the posts about owb's on here. I dont care if your wood is free . You still have to cut and stack, stack and cut and then cut and stack some more and you'll have to do two or three times as much with one of those pigs . Next youll have to deal with water chemistry and pissed off neighbors. There are plenty of wood hand fired boilers out there used and new for less money if your in love with wood. I used to burn a wood coal unit and loved it , free wood ect.... Then I started to realize how much time it actually took,OMG. I used seven full cord last year and it wasnt even cold. Ibought a used EFM ($4000) 1k for a chimney and misc. stuff . So far this year ive used almost two ton at $200 per. Im not trying to sell you anything but I think your options are as follows:
1) OWB ----> Bad option (read endless posts here)
2) Hand fired wood or wood coal-----> Good option
3) Stoker boiler-----> Great option and youll never regret it. Cut your wood and sell it to buy coal, youll make money!