But he says it will take big offers for FC Halifax Town to give consideration to any bids.
The Shaymen finished last season in the play-offs but were defeated in the Eliminator at eventual Promotion Finals Solihull Moors.
The manager wants to go one better next season and is happy with business so for.
But he is wary of the threat from elsewhere - and predicts clubs could come sniffing before the start of the new season.
Millington has spoken to the Halifax Courier about the summer so far and in an interview said the price must be right.
"There are players who will attract the attention of clubs with stronger finances,” he said.
“But they'll have to be very strong offers to make it worth our while because ultimately, we want to be successful in our own right and these are the lads we've selected to help us do that."
There may not be a wave of new faces coming in with the manager already boasting good numbers.
He said earlier this month: “It is a lot less of a rebuild, that was the plan a few years ago to try and secure people on longer-term deals
“We’re seeing the fruits of that long-term planning now. If we were to start the season today we would have a really competitive team and a strong bench.”