The hard part is know who are the sharks and who are the reputable real estate investors.  

Anyone who has some good plumber referrals would be much appreciated!  

For example Kansas City is a good market for turnkey investors as long as you work with a truly reputable and trustworthy company. 

If all he cares about is his own reputation in the market he will only hurt your position.

I am looking for a real estate agent or broker who has worked with investors before and who can connect me with reputable property management companies and investor contractors.

Also, I am looking for good reputable Real Estate agents in the Sherman/Denison area.

@Mallory Guerrero,The only way I would ever allow this, is if they were a licensed tradeperson  (plumber/electrician) with many years of experience, 99% won't be, so when in doubt-- No. 

I gave him my plumber's number.

Each one is different.As far as contracts, if you work with a  reputable wholesaler (may be under a co-wholesaling agreement), you should be able to see how he/she writes their contracts. 

My recommendation is that yes, you need to read and learn about strategies in wholesaling (follow a reputable wholesaler with a track record,) but also how to deal with people and negotiations.