Once you own bitcoin wallet or other crypto currency, thinking of how long you can maintain your wallet follows this steps,
First send your seed phase or private keys to your emails, also use them to compose a little song only can listen anytime, write it down in your diaries, and makes sure have a google doc to save your wallet keys and other information.
Saving your seed phrase or password in your email is not ideal. Doing that means accessing your email is also accessing your keys. Emails can also be hacked easily. Writing your seed in a diary will be a good option if nobody can access the diary. You will be risking your Bitcoin if you write it on the diary that you use every time.
Also, the topic of the thread is confusing. I was surprised when I saw the cost of maintaining wallets because I know that wallets are not like a fiat bank account in that you are to pay maintenance fees. I suggest you read this thread because it might help to guide you on topic selection.
https://bitcointalk.org/index.php?topic=5425265.msg61387162#msg61387162