I need to know if I need more proof of value than an e-mail from the cemetery salesman.
Since the value is more than $5000, you will need the signature of a qualified appraiser (to attest to the fair market value) and a signature of an authorized financial officer of the church (to verify acceptance of the donation), on a form 8283. When you report the donation, turbotax will generate an electronic copy of the form for e-filing, but you will also have to mail a paper copy with original signatures to the IRS along with a cover page that turbotax will tell you to print out. (Keep a copy for yourself of course.) If you don't mail the paper copy with required signatures, you WILL get a letter from the IRS.
Here is the form so you can print it out and start documenting the gift.
Whether the salesman is a "qualified appraiser" for this type of property is something I can't answer. I think the fact that they actually sold for that price would be good backup, and would be reason to accept the valuation if you were audited. (You might have more of a problem if you wanted to value them at $10,000 each when the church only could get $4400.)
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