well, im no expert, but a ds is around.. 130 now? how much do u think it'll cost to fix that crap/replace it worst case scenario. Save up the money and just buy a new one.
Let me explain: i can get DS lites for ~20 dollars USD, various issues causes them to be sold at a low price:
~top screen broke BUT STILL WORKS
~bottom screen broke BUT STILL WORKS
~bottom screen fuzzy BUT STILL WORKS
~SLOT 1 BROKEN everything else works fine (I NEED HELP W/ THIS! I think its the pins in the cartridge slot.)
~Hinges broken (but still works, somehow)
~Cracked Screens (powers on)
~Unit does not power on
~Unit left/right shoulder buttons fail to respond (works fine)
...etc, easily fixable, yes the parts are hard to find as you stated, $30 for a new screen? id rather buy 2 broken DS's, take the good one out of one, and put it in the other. So thats around $40 for a DS and got some spare parts left.
Dailun: you said you have repaired over 50 DS, DS lites, clearly you have experience in repairing nintendo DS. Thats why i was trying to find professionals, people that could help me fix them.
I have since "retired" from doing NDS repairs/rebuilds because it is not "worth my time".
I only maintain a spare parts/loaner inventory for the friends and family that I have sold/given them to.
I did sell several units in the early days but as time went on it was harder and harder to get the parts that I needed and I couldn't justify shelling out $50.00 for a used unit just for the logic board.
So then I would end up with several sets of parts that were good but not enough of the critical parts that were needed to make whole units. (ex. 4 good top screens and no logic boards)
It might be easier now that the cheap clone shells (cases) are coming out of China. When I started this the only DS Shells available were the shock shells. Nice as they were, no one wanted to pay $40.00 plus labor to re-case a cracked hinge unit.
Not to discourage you, but after all is said and done, I will have "made" about $10.00 per unit but I do have 4 or 5 complete units left over for loaners. I have "churned" through a couple thousand dollars between buying broken units, new spare parts, replacement chargers/stylii, etc.
So, it really depends on what your time is worth and how much you expect to "make" on each unit.
You also have to compete with the fact that Nintendo charges about $75.00 flat for repairing an NDS.