With the help of an experienced realtor would be best.
However, if you need financing, you'll also need a great mortgage person and a pre-approval (not a pre-qualification). Certain foreclosures require their specific lender pre-approvals.
Usually, your agent recommends a good mortgage person.
If buying cash - you'll need to have a proof of funds - your bank statements showing you have enough cash to buy (purchase price, closing costs and some reserves).
Hope this helps,
Beachfront Realty, Inc. - Florida