Defenders Nick Fenton and Will Haining have already left the club, with further departures expected as budgetary constraints at the Globe Arena begin to bite.
But Bentley, himself a former Shrimps defender, insists he is not a man to shirk from a challenge.
"There is no doubt it is going to be tough because we will have one of the smallest budgets in the Football League and we may lose a few more players yet," he told the Morecambe Visitor.
"But at the same time I am looking forward to it in many ways.
"I've always liked a challenge in life and this is going to be the busiest pre-season I've ever had without a doubt.
"But nobody will work harder than (assistant manager) Kenny McKenna and myself to make sure we get in the right players at the right cost for the club.
"There is no point sitting back and sulking about things, you have to face a challenge head on and that is exactly what we will do.
"We have watched loads of games in recent weeks and are going to a load of play-off games over the next few weeks in the leagues above and below us in our quest for players we think will fit into the club."