Coin-Trust fees by example - how much you pay and to whom

Money likes counting, and an honest service shows the count up front. Coin-Trust fees consist of three parts: the platform fee, the guarantor's rate and network gas. Let us take each in turn and calculate with concrete numbers so you know in advance how much each side will receive. For the overall picture of a deal see the lifecycle.

Three parts of the cost

The first three are deducted from the deal amount. Gas is paid on top, in the network's coin (what gas is).

The calculation order

The contract always calculates in the same order:

1. Platform fee = 1% of the deal amount.
2. Remainder = the amount minus the platform fee.
3. The guarantor's rate is calculated on the remainder.
4. The pot = the remainder minus the guarantor's rate. This is what is split between buyer and seller.
5. The seller's share is calculated by subtraction: what the buyer did not get goes to the seller. Because of this, rounding cannot "lose" a single token unit (why so).

Example 1. A successful deal

Amount 1,000 USDC, guarantor base rate 2%. The buyer confirms receipt.

For comparison: with the minimum base rate of 1% the seller would get 980.10 USDC (the guarantor - 9.90).

Example 2. Cancellation by agreement and expiry

Same conditions. The parties mutually marked cancellation (or the deadline passed and someone closed the deal).

Note: the buyer gets not 1,000 but 970.20. The platform and guarantor are paid for the deal having been processed and having taken up resources.

Example 3. A dispute

The guarantor's dispute rate is 10%. The guarantor issues a ruling.

First: platform 10, remainder 990, guarantor 10% of 990 = 99, pot = 891.

You can see that the cost of the dispute is shared proportionally: the side that wins more gets more, and the "cost of arbitration" proportionally reduces each share. How the guarantor decides - in the article arbitration design.

Example 4. The guarantor did not answer for 30 days

The emergency exit: the pot is split in half and the guarantor gets nothing.

Example 5. The offer was withdrawn before acceptance

The deal "never happened": no fees are taken. If the buyer already deposited 1,000 USDC, they get all 1,000 back.

Summary table (amount 1,000, base 2%, dispute 10%)

And gas?

Gas is a separate expense for each transaction. A typical deal has several:

• (for an ERC-20 token) the approve step, if needed (why);
• creating the offer;
• accepting the offer;
• confirmation (or cancellation, or dispute).

For the network's main coin (ETH, POL, BNB) approval is not needed. On Base and Polygon each transaction costs pennies, on Ethereum noticeably more (comparing networks, why L2 is cheaper).

How to choose the guarantor's rate

• The base rate is the payment for "readiness": the guarantor watches the deal and takes it on even without a dispute. A guideline is 1-3%.
• The dispute rate is higher because the guarantor spends time on the analysis. A guideline is 5-15%.
• A rate that is too low may fail to attract a quality guarantor, one that is too high will scare off the counterparty (how to choose a guarantor).

What to read next

Compare the calculations with real scenarios: a freelance project. If you are curious how the contract calculates without loss - integer math and rounding.