Door to Door sales - Pitching Home Security Doors for Sole Trader

I am potentially starting a new business relationship with a sole trader "Tom" in construction. The trader is a very skilled construction worker and has undertaken work on good projects. I believe that there is a market for home security doors. Can I simply freelance for Tom and receive payment from him if I successfully win a customer? I know I must register for self-assessment and pay some income tax. Do I need to set up my own company and contract out my services to the Sole Trader ("Tom")? I have worked as a self-employed contractor in financial services before. I worked for an "umbrella" company that was paid money by the contracting agency. The agency itself had an arrangement with the bank. The bank > agency > umbrella company > myself. I did at one point incorporate my own LTD Company to "skip the middle man" of the umbrella meaning the Bank paid the Agency and the Agency paid me. Should I restore my dissolved company? I want to do this legally compliant.

Hi

You may wish to consider forming a business partnership.  
This is declared in the individual's self assessment tax return (SA100) on supplementary page SA104 (partnership) and on a partnership SA800 tax return each year. 
Alternatively, you may wish to be subcontracted to this trader and declare your self employment income in a self assessment tax return.  
We can only provide advice on personal tax in this forum.  Limited companies fall under Corporate Tax, which we cannot advise on.

Thank you