If the property is listed 95% of brokers require their agents to have the seller sign an exclusive right to sell - which means they will handle the deal and will get their commission (both the seller as well as the buyer side of the commission). You going to the owner won't save the seller any money & will piss off the agent and they will post likely advise the seller to not sell to you (especially if you are considerably under the listing price).
Since you don't have an agent and I assume you aren't one - why not call the selling agent (or better yet call an buyers agent that works with investors) and tell them what you are thinking for an offer (i'd go low) and keep questions open ended to see what info if any you can get? Although agents seem to be more chatty with other agents - letting things slip like why the seller is selling - how motivated they are etc.
If you go through an agent (theirs or your own) - you won't need to hire an attorney to write up the purchase & sale contract.
Or - you can wait until the listing expires or cancels and then contact the seller directly to see if you can get a deal done.