The Fleet had an impressive first campaign back in Non-League’s top-flight, finishing sixth before beating Aldershot Town in the play-offs.
The semi-final trip to Tranmere Rovers proved to be one step too far for McMahon’s side but they will have plenty of eyes on them next season.
And the boss insists that the club will not be saying goodbye to any of their star players with keeper Nathan Ashmore reportedly interesting a number of EFL clubs.
McMahon told Kent Online: ”We won't be selling any of our players."We don't need to - we're looking to get stronger.”
On the strength of the National League next season, he added: “Chesterfield and Barnet are two good sides and they'll be looking to bounce straight back.
"Salford have got the backing of the Man Utd boys so I'm sure they'll be a very tough outfit.
"They'll be looking to go for promotion straight away and it'll be a tough league. It always is."
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