Got all my domains on auto-renew or paid in advance, no excuses, no BS, just do it.
If finances are an issue, perhaps you should dump those domains because they aren't making you any money in the first place, not anything worth worrying about anyway, sheesh.
it's best to keep all your important domains registered many years into the future.
I have one domain that people wanted so badly at one time that they kept emailing and asking to buy it almost continuously. The best offer they ever made was $5K, and I think they even tried to hijack it once. I knew they all had it on back order so I paid
20 years in advance just to make them quit asking and also so I'd never let it lapse and lose it by accident.
That domain comes up for renewal in 2016!
Got another similar domain that I had to people trying to get that renews in '14, it was only a 15 year future buy :)
Another one renews in '17 from it's purchase in '05, but that too was a special case.
Only did those way out multi-year purchase on 3 domains. I don't go usually go crazy with multi-year purchases unless I know I'm never letting it go and want to really make sure I don't forget to renew it, and as mentioned above it stops people from asking if you want to sell it. My typical renewal is 2 years just to save on time and a little money.
What if it's not "you" but "your executors"?
Forget the domain name, your server bill will probably not be paid, the account will be dead, your site will vanish, the SE positions and traffic all lost. By the time the executors figure it all out the whole thing will be worthless unless you plan in advance to keep it running in your extended absense.
FWIW, as I recently learned with an extended serious illness and lengthy hospital stays, you should have your entire life and business, let alone domain names and hosting accounts, set up for perpetual billing to cover your sudden and unplanned inability to attend to such matters. I already had everything on auto-pilot so there were no surprises for me. If I hadn't been setup for everything to perpetually pay the bills, I'm sure someone would've turned the lights off sometime last summer! ;)