I can only say this much...do NOT send your money in until the product is ready to be shipped and there is (are) picture(s) to prove it.
I learned my lessons with av123 so I know. 
There is also a flip side to this. When someone orders a pair of speakers, doesn't pay anything up front then backs out after the speakers are built. This leaves the person who built them out not only their labor but the cost for parts, materials and supplies.
And you can't just sell them to somebody else. The chances of somebody else wanting that speaker in that particular finish (whatever it is) and willing to pay for it when they didn't commission it are very slim. How many times have you seen somebody trying to sell a pair of speakers that they were stuck with waiting 6 to 12 months for a buyer then having to drop the price to less than what the parts cost them just to sell them?
You see, I've learned the hard way too but from the opposite perspective of yours.
What is needed is a method that would protect both parties. Maybe a version of how the bank my dad used to deal with handled construction loans (at that time dad was a general contractor building houses). They would approve the entire loan but would not release all the funds up front. The would release the funds in three parts with 1/3 up front then the other 2/3 at two intermediate points during construction.
With speakers it might look like this:
The buyer puts down enough to cover the cost of materials and supplies to build the cabinets.
Once the builder demonstrates the cabinets are built, the buyer sends in an additional fee to cover the cost of finishing the cabinets (this could be the cost of materials and supplies if the builder is finishing the cabinets or the cost of getting the finish done if it is outsourced).
Then once the builder demonstrates the cabinets are finished the buyer makes an additional payment to cover the cost of components (i.e. one of Danny's kits).
Once the speakers are finished and the builder provides proof of the finish the buyer pays the remainder of the price, including shipping and packaging costs (if the speakers are being shipped) and the speakers are delivered.
Just something to think about. Remember, there are valid concerns on both sides of the transaction.
Mike
