now working as/at the local home improvement store

[Silverobama]

I wrote the following sentence. I have two questions about it:

It is not unusual to find someone with a bachelor's degree, who just a few years ago enjoyed a salary of $80,000 or more annually, now working as an hourly employee at the local home improvement store or behind a counter at McDonald's.

I wrote this a few years ago when I read something similar on the newspaper.

a) Could you please tell me the grammar of the word "Working" here. Is it "find somebody working" here?
b) The second question is about the yellow "the". Are both "a" and "the" equally good here?

 

[teechar]

I wrote this a few years ago when I read something similar on in the newspaper.

Is it "find somebody working" here?

Yes.

b) The second question is about the yellow "the". Are both "a" and "the" equally good here?

I don't know what you mean by "equally good", but they're both possible.

 

[Silverobama]

I don't know what you mean by "equally good", but they're both possible.

In my context, which word is better "at a local..." or "at the local...."?

 

[teechar]

"the local home improvement store" = the only such store in the area.
"a local home improvement store" = some such store in a particular area. There needn't only be one such store.