I did a shoot for a local church's 75's anniversary a while ago free of charge. I got a check in the mail today from them for $200 and a note asking me to send them an invoice for my services, as well as asking if they could continue to use me for special events. (I didn't think the photos were anything great, but they liked them) This got me thinking about whether I should actually make a company name & register my services into a business venture. Also got me thinking about putting some photos on istock or some site to see if any of my stuff sells. (anything to get me out shooting on a regular basis to improve) The above thoughts got me thinking about putting a watermark on my photos that I plan on selling (or trying to sell for that matter). Is it really necessary at this point or should I wait until I get some kind of real business going.