I am not an accountant but if my logic is correct you could only deduct the $375 you actually spent. The $1000 you donated wasn't really "your money" it was money from a group of people. Since that $1000 was not part of your taxable income I don't think you can use that as a donation. However the money you donated personally ($75) and the $300 you spent to collect the $1000 you donated should be able to be listed as a donation as long as you have receipts to prove it.

On the other hand if you can prove you donated $1000 you might be able to declare that full amount.

Kind of a grey area for sure. I figured if nothing else I would bump you to the top so hopefully you can get the correct answer from someone who knows.

Another free bump - come on someone who knows tax code - how about a quick answer on this one for "swampfire".

I'm far from an accountant but agree that you shouldn't claim other people's donation. I think it would be okay to deduct $375 and maybe more for any needed maintenance on the machine. The important thing would be to keep good records of everything in case you get audited. It's not a lot of money so I doubt you will get audited over it.