I'm trying to migrate away from my Multibit Classic wallet. Recommendations I've read say to setup a new wallet with other software (I'm trying Electrum) and then send the BTC to the new address. I've got about 0.95 BTC.
It's not been easy because the transaction fee in Multibit Classic is set too low, so I've had to get the private key to my wallet into Electrum (either sweep or additional wallet). This has been complicated because Electrum doesn't like the format of the key from Multibit Classic so I've had to find a website to decode it.
I am now in a position to send the BTC, but when I preview the transaction, I see my transaction fee is 0.08BTC - that's around $300! It would seem it's because the transaction size is large, as I collected by BTC through altcoin mining a couple of years ago, so there are lots of source transactions (141) which makes my transaction around 22KB. Would that sound right? See below.
Can this be right? I can't believe I'm being charged $300 in transaction fees! Please help!
Based on current transaction fees and the huge number of inputs you are sweeping, that sounds about right. The network is being spammed pretty hard right now (likely to do with the Bitcoin Cash drama) and on top of it, the Bitcoin hash rate has dropped and blocks are being published slower than 10 minutes per block. You may be better off waiting until the congestion dies down; fees may drop considerably.
The other thing you can do, as stompix mentioned, is import the private key to a wallet where you can set a manual (low fee). It could take days to confirm, but some miner may publish your transaction eventually. If not, you can always re-broadcast it with a higher fee. Good luck!