After two wins on the bounce in the league, United were looking to keep their good early season form going while Hailsham would be looking for a first victory of the season and a first FA Cup victory since 2008/09.
Russell Tanner, Aaron Capon and Paul Rogers all made their United debuts, while there was a first start for youngster Macaulay Gray.
Bailo Camara, Rogers and Capon all had half chances within the first twenty mintes, but it was Capon who would strike first.
The pacy winger nipped in behind the visiting defence and beat the onrushingSheldon Levitt to the ball, poking the ball past the Hailsham ‘keeper and placing into an empty net.
The lead was soon doubled as former Hailsham captain Ashley Jarvis was allowed space in the centre of the pitch to take the ball forward and unleash an unstoppable drive from 30 yards that comprehensively beat Levitt.
From the restart, Hailsham attacked and came close to a leveller as Sam Divall curled an effort just over the far post of Tanner in the United goal.
On 35 minutes, Jarvis got his second of the afternoon as he was left unmarked to place a sidefoot volley past Levitt following a Wes Tate corner.
Hailsham kept pressing forward looking for a way back into the tie and Dan Pollard had to be alert to make a well timed block from inside the 6 yard box.

Into the second half and it was Hailsham who pulled a goal back as Sam Divall curled an effort in off the underside of the bar to give ‘The Stringers’ hope of a comeback.
A brave block from Hailsham captain Lee Jules denied Dave Smart’s thunderous volley, before Hailsham attacked with their best spell of the game.
Former United man Jack Divall was twice denied by the United defence, firstly by a last gasp block from Pollard and then saw a rasping drive beaten away by Tanner a few minutes later.
With just over twenty minues remaining, Capon found his way into the area and calmly slotted across Levitt to restore United’s three goal advantage with his second goal on an impressive debut.
Paul Rogers had two good chances to make it five, but saw one effort deflected wide and the other go wide by a matter of centimetres.
Hailsham pulled a second goal back with eight minutes to play as Jamie Salvidge headed across goal and saw his effort hit the post and go in, despite the best efforts of Tanner.
With the game close to a finish, Rogers got the goal that his performance deserved as he sidefooted high into the Hailsham net.