I can appreciate the dilemma, but providing PM services with contract labor carries a lot of risks you may not have anticipated. My comments here are only intended as general background. I encourage you to consult with an attorney licensed in your jurisdiction to get more detailed advice:
1. If this contract PM is working mostly or exclusively for your firm, and does not have his or her own independent business, the IRS could re-classify the PM as an employee and assess your firm for payroll taxes. This is a high value audit issue for the IRS.
2. Likewise, if your PM is considered a statutory employee, your firm could be liable for overtime pay despite your efforts to negotiate a fixed hourly rate or max fee for the service. This is real gray area, as there are exemptions for "white collar" employees, but your facts may not fit that exemption.
3. Your professional liability insurer won't like the arrangement either. While you probably will have coverage for your vicarious liability, you won't have recourse against the contract labor PM for his/her mistakes unless that person also carries insurance (and they usually don't).
4. You may have a risk under your state professional practice act for delegating professional services to someone who is not your bona fide employee (i.e., W-2 employee). Some jurisdictions might also require a written subcontract with that contract PM before you could legally seal and sign any professional documents prepared by that person. That written subcontract may help with problems 1 and 2, but won't absolutely protect you if it is evident that the person is working under your direct supervision and control, works mostly or entirely for your firm, and you are providing all the "tools of the trade" such as cell phones, computers, software, and so on.
5. Unless this person is someone you know and trust well, it can be very difficult to manage a contract PM, and their loyalties may not lie with your firm over the long term. We have seen many situations in our law practice in which that contract or temp employee caused major damage to the project or client relationship. The employer (or its insurer) ends up writing the check in every case. If you give this person a business card with your firm name on it, you may well be held responsible for anything that person does in your name even if that exceeds the scope of the authority you intended to grant.
If your work has picked up to the point that you need the help, it is better to increase your fee quote to support the added burden of payroll taxes, benefits, and compensation, so that you may bring your PM on board as soon as you can do so. Until then, treat the PM as a subconsultant, which means a formal contract, insurance requirements, and all the other things you require of other subs.
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P. Folk
Attorney
Folk & Associates, PC
Phoenix AZ
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