I know there are many companies and individuals who offer these services however I would like to know what questions I should ask so I know what I am getting and what steps I should take to make sure my site stays secure in the future. 

I have a monthly membership on that site $100/month to check 100 properties.

All the units looked good and were clean and kept up when I walked them.

I stumbled upon this site brainstorming an idea I want to make a reality and thought this would be a good place to look for suggestions/advice.

Been reading the site for a month or so and decided to get more involved.

Hello and welcome to this site Anthony! 

I like to think I'm helpful in other ways too like helping them move, load up trucks, clean up the house, etc. 

It's all give and take and cost/benefit analysis you need to consider/decide upon.As others have said, go to local REI meetings, meetups, or just try to connect with people here and see what value you can provide these people in exchange for their help.Maybe you can re-design their website for them, or do some bookkeeping, or clean their office, or whatever skill you have that you think they might benefit from. 

It must be a feature that shows up only for paying members on this site.

:I use On-site, check them out.