There are good mail services, and they will screen your mail/pay your bills etc.
We always had friends or relitatives handle the mail and bills. In turn we handed the affairs for some of our friends when they were cruising.
We did find that forewarding mail was often not reliable. Since we had guests visiting us often, we usually sent mail and important documents that way. Probably the worse was U S Postal service.
DHL often can get mail to places that others may have problems with. I would suggest that once a month a package of important material be sent. In todays world mail of electronic transfers seems to be almost superfulious. However secure transactions are probably best handled by someone stateside.
When we were in Spain for the winter, there was a strike of the postal workers and mail was burned. A number of our British friends didn't get their pension checks because of this.
Bob Austin