Several different busines pursuits--1 LLC, 1 LLC with DBA, or LLC for each

Just started a seasonal service based company last year. Currently, looking to open up a retail location with residential units above, and manufactoring a product that will be sold in tourist destinations (alot going on.) The seasonal company is an established LLC in the state of MD. Is it plausable and advised to create a single LLC, i.e Spectrum Enterprises LLC, and have each individual business setup as a DBA ? Should I have an LLC established for each business (state of MD APPROXIMATELY $200 setup and a yearly $300 compliance fee for LLC). I look forward to hearing your feedback and any thoughts/suggestions offered.

Every state is different, but in Texas you can use an Assumed Name Certificate.

It works like this: a single entity is established (Seasonal Goodies MD, LLC) which files all the tax papers for both state and federal. Next, file a A.N.C. for each side business, you can have several. For tax purposes, the side business is like a "child" of the LLC.

Each side business can be treated as its own business with its own phone number, business address, credit line, bank account, etc. Be sure to keep a separate accounting file for each side business. As you establish each side business you'll be asked to send a copy of the DBA certificate. You'll send in both the LLC papers plus the Assumed Name Certificate. Together, they equal a DBA for the side business.

When it comes tax time you pool the information. A single tax form is completed under the name of the LLC. You then attach to that form a supporting form for each side business.

Seasonal Goodies MD, LLC (taxes filed under this name) - Net Profit $ 100

Larry's Crab Hats (supporting tax form) - Net Profit $ 20,000

There are three main reasons to create separate LLCs:

(1) The different businesses will have different owners
(2) The different businesses will have different management structures
(3) You want to protect the businesses from each others' liabilities.

Under #3, here's an example: let's say that one of the goods sold to tourists is defective, somebody dies, and the company is sued. If they are all in the same LLC, then the victim can potentially get all of the company's assets, including the building. If, however, the ownership of the building is in a different LLC than the company doing the manufacturing, and you maintain a formal separation between the two -- i.e. the manufacturer pays rent to the building owner, etc... -- then the victim can only go after the assets of the manufacturing company, but not the building.

Chris & Hondo both make great points, especially Chris. Some other considerations... In California, every corporation pays a minimum of $800 in taxes (even S Corps). So, you'd pay that three times. If you need to have an accountant file your taxes then you have to pay that 3x too. Also, another argument for one business (assuming all three businesses aren't S corps) is that under one company you can net losses in one endeavor against profits in the other- without limitation.
If you do decide to go with one umbrella/holding company for all three businesses, make sure you track all of the businesses independently. If you ever want to sell one of the businesses, you'll want to be able to show its financials separately.
All of this said, Chris's three points trump all other considerations (particularly if you have a high risk/liability company.

Good Luck,
Chris