Dear all, thanks again for your help in advance.

Here are some photos of what we have:

The house is in San Francisco (built in 1930s) and it's about 1.2 miles away from ocean. One of the bolts on the wall mounted metal step ladder somehow became loose. Since the crawl space is very damp and the concrete wall is sort of crumbling, my general contractor did not want to help me to get it repaired. If I am to DIY to get it repaired, what would be the best way (tools and bolts, etc.) to get it repaired? Thanks!