multiple access points vs stronger antenna

I am designing a wireless network for a site. IT has two floors and is
in an L shape. The outside lines are 200 feet long. The inside lines
are 100 feet long.

I was intending on using antennas to increase my gain and reduce the
number of access points I would have to deploy. However, one of my
vendors suggested access points everywhere instead. In their design,
they have access points every 20 feet or so. In my initial design, I
have WAPs every 80 feet or so.

The wireless network will not carry a lot of traffic, but should be
available in most places for good network connectivity.

I was leaning toward the lightweight access points (ala airespace) but
I wasn't sure if there was another vendor who might also have a good
product with central configuration.