There is nothing wrong with brick, but you don't like it. So it is the wrong material for your builder to use.

Couldn't he build the ramp now?

With brick steps, all those mortar lines can play tricks with an old guy's eyes. If I were building steps for my grandparents, I might color them different colors to make them easy to differentiate, even in soft light. And even with three steps, I might get creative on how to place a railing alongside.

You are writing the check. Pouring the concrete for a ramp shouldn't be more of a challenge than the bricks, but I don't know what codes a ramp needs to meet.

There's my fiftieth of a buck.

Wood steps now and a wood ramp later makes the most sense.

What you need to consider before the final plan for the house is built is just how a ramp will be able to fit (if at all) into your current garage.