Pretty new to the platform.

I advise newer and existing agents to hire a sales coach or mentor before spending money on leads, whether it's through Zillow, BP, or some other real estate-related platform. 

Yes, there are a few platforms that do that for you.

My current platform charges $55.

It sounds like you bring a ton of value to the platform given your past experience.As far as where to start, that is difficult to answer without knowing more about what you're looking to accomplish and how hands on/off you intend on being with your investments.Turn-key companies have tremendous appeal given the fact that they target below-market value properties, handle property management and project management.

Quote from @David Kulbacki: I have never heard of any platform restricting a guest from signing an agreement.

I look forward to learning from other professionals on the Bigger Pockets platform. 

I don't know what the land market is like in Colorado, but in California, there is land that you need to put on the market because the buyer profile is someone who comes out of the woodwork and who you'd never find without putting it out there, so I use platforms like MLS, Crexi, AIR, Loopnet and Costar.

Check their reviews on multiple platforms, make sure the reviews range in dates, check bigger pockets find a lender and ask other investors who they have used. 

New to the platform and just getting started in the real estate world!