Hancock County-Bar Harbor Airport (BHB) overcame significant financial challenges to remodel its facilities. And in the end, the small Maine airport doubled the size of its terminal, upgraded its security area, added new customer conveniences and generally made the building more aesthetically pleasing and energy efficient. The $2.5 million facelift, completed late last year, increased BHB’s terminal from 5,000 to 10,000 square feet. It also created separate arrival and departure areas — a critical upgrade for small airports, due to post-9/11 security requirements. (BHB logs about 34,000 total operations annually.) But the project required intense number crunching to keep it within budget. A collaborative effort by airport officials, the contractor, design team and engineering consultant cut nearly 20% from the original $3.1 million cost estimate.