Wheelchair Ramp for Landon

My nephew Landon was diagnosed with Juvenile Dermatomyositis in 2011. While some children go into remission with this disease, my nephew has yet to go into remission. The damage the disease has done to his muscles and tissues leaves him unable to stand, support his own weight, or walk. His only means of ambulation is with a wheelchair. My sister is no longer able to lift him from his chair and carry him up the steps into their house at the front, side or back doors of their home. 
We are working with an organization called Wheelchairs for Kids who is attempting to help us get an ADA aluminum wheelchair ramp installed at my sister and nephew's house. The organization has found a generous supplier who has discounted the materials and will even donate part of the labor to install the ramp, but the sponsorship amount is $4500.
This ramp is one that can be dismantled and reinstalled if the family moves, or when Landon is out on his own, and being aluminum it is sturdy and safe. Please help our family get this needed ramp to ease in Landon's movement in and out of the house. He still must go through weekly infusions, treatments and rehabilitation in our fight to hopefully have him go into remission one day.