Contractor taking me for a ride. Need help from exp Investor ASAP

[Zain B.]

I need some advice dealing with a contractor. I have started renovation on my Maryland property and I hired a contractor. We mutually agreed for him to charge $11,500 for his labor. I would provide all materials and have my dad manage the project alongside the contractor. Any material request / shortages, my dad would run and grab it from home depot. The contractor came to work for a couple of days and did work as it relates to demolition of three bathrooms / some walls, taking out old laminate flooring and creating framing in one room.

We had agreed that I would pay him $2,000 relatively shortly once he started the project and than will give him another $3,500 half way through the project and than pay him another $2,000 75% of the way and the final payment upon completion of the project. He agreed and started work. I gave him the $2,000 check and once he cashed his check, he started making excuses and not coming to work saying that he fell sick (which lasted for 3 days). He just texted me saying that all contractors charge 35% upfront and if I could not provide the 35% upfront, he would not work anymore. He is not a licensed / bonded contractor. Someone who knows his trait and seemed like a trust worthy guy. 

My suspicion is that I am getting played. I am afraid that he has found another contract or his sub contractors are not available. He wants another $1,500 and than will make us run around for completion of this job. Is my suspicion correct? He is not a licensed or bonded contractor. He is a great handyman that knows his trait. We found him in a home depot early in the morning (J Scott) strategy.

My question to you is, how do you work a payment scheme with your contractors? I am sure you have your set crew but if you were to work with a new contractor, would you give him/her 35% upfront? He also changed his terms after starting the project and wants 70% half way through the project. As mentioned earlier, he does not come through any reference. I found him in Home Depot. Should I give in to his demands or walk away. Any help you could provide will be greatly appreciated. I am going down to Maryland tomorrow morning to meet him. Apologies for the late night request but wanted to see if the community could provide any timely advice. Thanks in advance for your help.

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