All my bills are paid by timed auto payment or online or thru an app. If available I go paperless and can see my accounts thru my bank or their sites. If I get a check I photo deposit otherwise all SS and IRA payments are direct deposit. Doesn’t cover everyone’s needs but does mine.
There is America’s Mailbox
http://www.americas-mailbox.com/home/advantages
Also one out of Florida.
Hope you get all setup. Happy RVing.