What you sign and what it costs

Collecting NFTs means signing three kinds of transaction. Each one is short. Read it before you approve.

Accepting an offer. This is the one that moves money. The request does not spell out the price. It points at an offer by its ID, a long string. The price, the currency and the NFT are written in that offer.

• Accept a sell offer and you pay its amount and receive the NFT.
• Accept a buy offer and you hand over your NFT and receive its amount.

If your wallet shows only an ID, look the offer up before you sign.

Check the currency. An amount can be XRP or a token. A token called "USD" can be issued by anyone. A buy offer for "500 USD" from an unknown issuer may be worth nothing. The issuer address tells you which token it is.

Creating an offer. A sell offer with an amount of 0 XRP is a gift. Signing one hands the NFT to whoever is allowed to accept it.

Canceling an offer. This removes your own offer and returns its locked XRP.

Xaman's guidance fits all three: read every transaction before you sign it. Once it is confirmed on the ledger, it is permanent.

The cost of collecting. Each page of NFTs locks 0.2 XRP. Each open offer you place locks another 0.2 XRP. Ten open bids lock 2 XRP until they are accepted or canceled.

NFTokenAcceptOffer carries NFTokenSellOffer, NFTokenBuyOffer or both. Each is an NFTokenOffer ID, not an NFT ID and not a price.

Before signing, resolve the offer:

• ledger_entry with nft_offer set to the offer ID returns the NFTokenOffer: its NFTokenID, Amount, Owner and any Destination.
• nft_sell_offers or nft_buy_offers with an nft_id lists each offer's nft_offer_index, owner, amount and flags.
• An amount is a string of drops for XRP, or an object with currency, issuer and value for a token.
• Confirm the NFTokenID is the NFT you expect. Then confirm that NFT's issuer and taxon. See Checking a collection.

If the NFT has a transfer fee, the issuer's percentage comes out of the sale amount. The seller receives the rest.

NFTokenCreateOffer fields to read:

A buy offer fails with tecUNFUNDED_OFFER if you do not have the amount available. For XRP, the reserve counts against you.

Reserves. From xrpl.org:

A new account that holds one NFT and has one open offer needs 1.4 XRP in reserve. A transaction that would take you under the reserve fails with tecINSUFFICIENT_RESERVE.

Getting XRP back.

• NFTokenCancelOffer on your own offers. An accepted offer is removed and frees its reserve as well.
• NFTokenBurn destroys an NFT you hold. When enough NFTs leave a page, the page is removed and its 0.2 XRP unlocks.
• An account cannot be deleted while it holds an NFTokenPage. Burn or transfer each NFT first.

Related: Scams and signing, Getting reserves back.