Firstly it depends on what sort fo restaurant you are looking at setting up as was previously pointed out. Also what back gorund in business do you have?
One of the most important things to remember is that it is a business first. Consequently understnading the tax system for the state you are setting up in is very very important. Especially when you consider things like Federal government can offer tax benefits in certain states for setting up. Understanding what you can write off against your tax bill and so on is also very important.
Getting advice is a very important first move. Listen to people whom have been in the hospitality industry for a a number fo years.
People who set up or buy restaurants often fall in the idea of how hard can it be? Truth is that restaurants have the highest ratio of failed business to success in the modern world. Consequently lending institutes are often harder on interest rates let alone deposit ratios.
Because of the high risk involved I would suggest starting with a sure fire style (ie no risk style) restaurant as aopposed ot higher risk style. So for example mexican in California while faicng huge amounts of competition is not going to make too many waves.
Starting at 150 seater is pretty big considering you have no previous hospitality expirience. Do you understand any of the basic costs? 150 chairs plus back ups should cost in the region of $100 USd for moderate quality chairs per chair. Thats 15k on chairs, not including tables, menus, product, and other set up costs. Signage etc...all cost money.
Two areas you should not skimp on.
1) Finding a good restaurant manager whom can help guide you. Listen to the guy/gal make sure they have good references with proven success in their back ground. Their knowledge will prove invaluable in your first two years as oyu come to terms with suppliers, credits issues, beverage supply, customer and data base management.
2) Ensure you have enough capital to fall back on. You will probably loose money in your first year of operation, break even in your second and make a profit in your third if you are LUCKY. If you are unlucky (another Sept 11 - God forbid- comes along and world cash dries up so everyone eats in for a while)it could take 5 years before oyu make a profit. A good accountant will help you greatly in this.