Technically, you don't need to produce proof unless you're audited. For the cash ones, I'd write a note documenting what you paid, when, to whom, and for what and keep that if you can't get receipts. Not perfect, but better than nothing.
Yea. I have everything documented pretty thoroughly. I pulled all my CC statements and have everything all together in one place. The only thing I don't have documentation of (outside of my spreadsheet that has the date of purchase, method of payment [cash], where it was purchased, and notes about what it was for) is $245 for my wife's glasses at sam's club, and an $8 TB pre-employment test she took at the health clinic. I suppose we could follow up with the clinic to get a receipt, and have my MIL obtain a receipt from Sam's club (pretty sure they document everything through the membership card similar to costco), but it doesn't seem like it's worth the effort at this point.
In the event we get audited I could probably obtain those receipts. Although with how well I have everything else documented I would suspect any auditor would know i'm not trying to scam the IRS by claiming those 2 items. I've never been through an audit though, so I don't know if they require every single last receipt, or if they can look at the overall trend and just say "this guy has 99% of everything documented, with notes to boot, and has all his shit in order - let's stop wasting time and move on to the next person" or what the deal is. How anal are they? Do people legitimately document their $14k in deductions...then try to sneak in an $8 TB test they paid cash for?
I think i'm very unlikely to be audited anyway. All my medical expenses only ended up letting me deduct about $400 anyway, and the rest of my itemized deductions are all clear cut and everything is in order.
