18 The words “of purchase” are not in the text but are implicit. The qualification is spelled out explicitly in vv. 11, 12, 13. These words are supplied in the translation for clarity. An alternative translation would be “I put the deed in writing.” However, since the same idiom כָּתַב בְּסֵפֶר (catav bésefer) is used later in v. 12 with respect to the witnesses, it is likely that it merely refers to signing the document.
19 The words “to the purchase” are not in the text but are implicit in the idiom “I had some witnesses serve as witness.” The words are supplied in the translation for clarity.

In other versions

I signed the deed, sealed it, got witnesses, and weighed the money on scales.

I signed and sealed the deed, had it witnessed, and weighed out the silver on the scales.

I recorded it on a scroll, sealed it, called in witnesses, and weighed out the silver on the scales.

I signed and sealed the deed of purchase before witnesses, weighed out the silver, and paid him.

And I signed on the letter and sealed it, and I called witnesses as witness, and I weighed out the money on a set of scales.

And I subscribed the evidence, and sealed it, and took witnesses, and weighed him the money in the balances.

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