The nature of your need and type of agreement will need to be fleshed out of course. The costs to prepare the agreement will really vary depending on the scope, complexity and the provider and you are wise to have this done properly.
Obviously, purchasing legal services is not like buying an appliance in that you will not end up with the same product no matter where you buy it. That said, providers work in all sorts of ways. My firm, for example, will first discuss by phone then formulate a flat rate budget based on the specs that will cap out at some amount of attorney time to protect all parties. Other firms as is more traditional will work on an hourly basis.
You are in a good place to search for a lawyer and I suggest you call around to several and get a sense for how they work and how they price. I will link you to some info below and most of us here, including myself, offer a free phone consult so you should take advantage of that.
The law firm of Natoli-Lapin, LLC (Home of Lantern Legal Services) offers our flat-rate legal services in the areas of business law and intellectual property to entrepreneurs, small-to-medium size businesses, independent inventors and artists across the nation and abroad. Feel free to call for a free phone consultation; your inquiries are always welcome: CONTACT: 866-871-8655 Support@LanternLegal.com DISCLAIMER: this is not intended to be specific legal advice and should not be relied upon as such. No attorney-client relationship is formed on the basis of this posting.
You give no details other than the other party is a Vietnamese artist, who will be collaborating with you on a comic book project. Many details are missing: who works for whom? is the artist an employee or consultant? who is paying? is the artist free to work on other projects? for competitors? on the same genre? on the same characters? what is each party doing? is the artist just doing art? will you own it or both of you own it? where will be it be sold and how? will it be hardcopy or digital or both? and many, many more issues that need to be determined.
For a simple work for hire and copyright assignment, you might expect to pay $1000-3000 depending on how much negotiation is needed and what difficulties arise with legalizations.
I suspect you have many more underappreciated legal issues, such as publishing contracts, agency contract, licensing needs - both in and out, trademark and servicemark issues, business enity formations, business licenses, dba filings, etc.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.
You can spend as much or as little as you want on a contract.
Does the Socialist Republic of Vietnam actively enforce its IP / contract laws against its own citizens when a foreigner brings suit? Does it honor judgments from US courts?
When it comes down to it, when you contract with companies in emerging markets like Vietnam you are depending on the honesty and integrity of the person you are contracting more than the courts to force them to be honest.
You would be crazy to go into an agreement like this without a well crafted contract, in both English and Vietnamese, but if you think your artist is going to steal your idea if it becomes commercially successful, just don't collaborate with them. Trust but verify.
You should consult with an IP attorney in your area and maybe look for a law firm that has both US and Hanoi offices.
You need to find an attorney with labor and intellectual property law experience operating in the Vietnam territory, because you need to confirm the enforceability of such contract under the local laws. You will also need to know the form and substance to be included, because a contract that is valid in California for such artist services might be invalid in Vietnam. Further details will also be needed about the business terms between you and the artist in terms of payments, rights and deliverables. Once you have the business details confirmed, once you have an attorney with experience in Vietnam, then that attorney can advise you on the best way to enforce those business details in Vietnam.
The foregoing response is provided for general informational purposes only and is not a solicitation for business. Please retain an attorney if you need specific legal advice. No attorney-client relationship is established until both you and me agree to establish one, and neither transmission of information herein, nor the receipt of such information, constitutes an agreement to establish an attorney-client relationship.