Nick Montgomery feels four January arrivals would be the 'magic number' for Hibs.
The manager says the club are working hard behind the scenes to provide support for a squad stretched by injuries and players departing on international duty.
Montgomery cautioned that it can be a challenge to do good business in January, and reiterated budgetary constraints.
Additional funds, however, could be freed up by fringe players leaving before the end of the month.
“You only have to look at the squad," said the manager. "Anyone looking at the contrast between our squad and Hearts at the moment, you can see that they have a lot bigger budget than we have. And that means you can bring in more players to create strength in depth.
“With Josh Campbell going out, the magic number would be four. If we can get two, or one, that’s what we’ll work towards.
“We can only stretch the budget available so far, so that’s why we have to be clinical in our recruitment. We have got a couple of targets but it’s not easy to get quality players in, and to have clubs willing to let them come in for the budget we have available.
“We’re working really hard, and maybe one or two will go out to help that fund. It’s an ongoing situation but it’s the same at every club this time of year.
“Depending on if any players move on, there can be a knock on effect in freeing up budget to bring another player in. It’s really hard to say."
READ MORE: Montgomery reflects on Hibs progress and says signings key
Hibs are still awaiting Scottish FA approval on minority investment in the club from billionaire Bournemouth owner Bill Foley. And until that money is guaranteed, though, scope for spending remains tight.
“It’s been well-documented but not confirmed yet," said Montgomery. "There’s regulations to go through with the SFA, but until that’s guaranteed money…
“The club has been very clear on where that investment will go, it will go to improving the training ground and the stadium, and potentially some will go into the budget. Until that’s a guarantee, we’re working with what we’ve got, and that’s all we can do."
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