How much does it cost to add liquidity on Uniswap?

Could you please elaborate on the costs associated with adding liquidity on Uniswap? Are there any upfront fees or ongoing charges that traders need to be aware of? Additionally, does the cost vary depending on the size of the liquidity pool or the specific cryptocurrency pair being traded? Lastly, are there any potential risks or considerations that traders should keep in mind before adding liquidity to Uniswap?