This instructable is to serve more as an inspiration to build your own, as I did not fully document the construction (just worked with what I could get cheaply), so no exact measurements will be provided. But you are welcome to ask me questions about it and I will do my best to answer them.
To keep it as easy as possible we made the sides and base out of full sheets of plywood. The base is constructed out of 2x4's and topped with a piece of 1/2" plywood.
The front seat is a box constructed of 2x2's and skinned with plywood, with common porch lights that I found in the clearance section of home depot mounted to the side (notice the fancy cutting I had to do to get them to fit within the molding in one of the shots).
The detail work/pillars are just gazing ball stands from big lots (they had a sale on them for 6.50 each so we took them on the table saw and cut the side ones in half, and cut a quarter out of the corner ones). Below these is a piece of 4" pvc pipe, cut and glued to the side of the hearse.
Its really all about sourcing materials.
Since this is a static prop, the entire structure sits on 4 pieces of 2" metal pipe hammered into the ground with t's acting as axels for the 1" pipe going between the wheels (which are harbor frieght wagon wheels with hubs made of plastic flower pots painted black).
The small fillagry around the hearse consists of the pre-made wood adornments that you can find cheaply at Lowes/home depot.
These, like the rest of the hearse, were painted in "Behr ultra, high gloss, black exterior paint" which has to be the best paint I've ever used. Covered in one coat and held up to the elements year round.
Then we came back and detailed everything with antique gold craft paint (sponged on to look aged).
The curtains are made of fake crushed velvet thats cheap and commonly available at Joanns (use a coupon for this and the fringe, because it adds up). We replaced this every year, as the sun and rain took its toll on it, but it actually gives it more of an aged look if we had just left it on.
Btw... dowels make fantastic curtain rods on the cheap (you can see them in the disassembled photos).
Lastly, wire up the lanterns, throw in some flicker bulbs, toss on a skeleton, and a home-made coffin in the back and its ready for its debut.
The point of halloween prop making is the journey and experience of making the props and sourcing the materials, finding ways to use things that were never originally intentioned be used in that manner and just have fun! This is my favorite static prop I've ever made (and favorite prop only second to the fogscreen or pirate ship), and I hope the path ahead of you brings you as much joy as it has to me!
Again, feel free to ask questions and I will be happy to support you in your endeavors!
I will also update this if I find any more photos and plans (though unfortunately many got lost due to a hard drive crash).