I adverted it before 100% finished (still need to add gutters and do landscaping) and it worked out for me.

I am looking to advertize/ market for investors in my area in local newspapers and websites.

As for advertizing, it varies by city. 

I've always advertized my place as soon as possible.

High school or college kids just looking for spending cash is going to be a different story.As to duties, besides answering the phone, filtering email and scheduling, I had my assistant prepare correspondence, handing adverting, inspecting rental damage, contacting repairmen etc.

People will want to know what the ARV is for that property as a 3/3 right now.It's not the type of advert the people I work with would go for, but maybe you'll have some luck where you post it on Facebook.

I know I've seen other companies advertize this service but did not know if I wanted to get into this.

My plumbing contracting business was a success since I was always busy, made a great income and never had to advertize, just repeat customers and referrals.

On what I should put, or not put in the on-line adverts?

Those adverts may send you dozens of prospects every week but only a few ever invest with you.