Cold wallet, transfer fees

I am looking to buy another hold crypto for long term mostly BTC. I will be investing in ledger as cold wallet. Any downsides of ledger and what is everyone experice with transfer fee. Specially when transferring crypto back to exchange. Or are there any better ways to covert to fiat currency. In long term I am hoping I won't have to as crypto will be accepted at most places if not everywhere.

Thanks in advance