# FAQ

Source: https://soheil.fi/developers/docs/faq/

Short answers to what integrators ask first.

## Which tokens can be traded?

Any ERC-20 token the router finds liquidity for, and the network's coin. Tokens that take a fee on every transfer may fail: the quote expects the full amount to arrive.

## Can I charge a different fee per user?

Yes: send `integratorBps` with each quote, from 0 up to your key's ceiling.

## Where does my fee arrive, and when?

At your key's fee address, in the token sold, in the same transaction as the trade.

## What happens if the price moves?

The trade reverts below `toAmountMin`, and the user keeps their tokens. Quote again; a higher `slippageBps` helps on volatile tokens.

## Is there a testnet?

Not yet. Test on mainnet with small amounts; quotes are free and count only against your key's limits.

## Bridges, Solana and other networks?

Bridges come next, through the same contract and API. More EVM networks are added over time. `GET /v1/chains` is always the current list.