aging vinyl siding -- what to do?

[Mary]

We have a 1974 double-wide, yellow, with vinyl siding. In places it's fading and sort of peeling, and in general it needs something.
Would a power wash help things?
What about the peeling parts?
I notice the parts store on this site sells a kit to clean siding and then paint a coating on. Perhaps we should get that kit and have our handyman apply it. Does this coating last 10 years and renew everything, like the ad says?
Any advice from anyone would help. Thanks.