Writing off gear?
 

One does not necessarily "form" a sole proprietorship. In New York,
one goes to the county clerk's office and files a "Certificate of Doing
Business Under an Assumed Name", pays a fee, and that's about it. This
is generally known as a DBA (Doing Business As". But for the OP, not
even that is necessary. This is only necessary if you are going to
advertise or be paid under an "assumed name", for exampe "World Tours
Photography" as opposed to just having a check made out ot "Carlo
Coggi". For a DBA, you use your Social Security Number instead of a
EIN. This has a few advantages. First, all of the income/taxes are
reported on your personal income tax form. Second, if you file for a
EIN, you come under the juristiction of the state labor department
because of the potential of having employees.

If you are using "Carlo Coggi Photography" as your name, argueably, you
don't need a DBA because you don't have an assumed name, but it sort of
depend on your your bank interprets it. No one else really cares,
except maybe another Carlo Coggi.

If you file a DBA, then you need to open a separate bank account in
that name, which is a pain for only 1 transaction.

If the income is a one-shot deal, or even a reasonable number of
transactions, just have the checks made out to you and use your own
SSN. In this case, you don't have to do anything at all, unless your
local municipality requires it (but what are the chances that they find
out on a 1-time deal).