I hate to just repeat what everyone else says but your better off with multiple locations with 99 in each one. ONE, if you dont have a lawyer you are totally screwing yourself... either you hire one now or when your in jail... but its harder from jail.
Second what happens at the raid is no matter what, they will cut down your plants, make a mess, maybe break some bulbs... either way its all fucked and I hope if it does happen you have money saved for what comes next. Then you may or may not get charged, if the cops didnt totally hate you then you may not get charged for months. If they have it in for you they will call the DEA in a second for that kind of plant count. When you get to court youll have to present your collective argument, they will hassle you about knowing all of your patients and finding out if they were also involved in the growing. If you have a good lawyer this may go ok but then you'll piss off the DA and maybe then they call the DEA. This all mainly happens because of the attention you attract by having that many flowering plants, takes up a lot of space and that means that many more cops are showing up to the raid. That much more pressure on the DA to nail you for being so cocky. I know a specific situation where someone called on a collective grow and when they got there the cops said they couldnt just let it go because it was so many plants. They even tried to talk it down to the DA but the charges were still filed. So really if you decide to do this, get a GOOD lawyer, donate money to your community and maybe kiss ass to the local cops cause youll need all the help that you can get.
All this vs having 99 plants at a house or a small warehouse. Chances are if you get knocked it wont be the "important" raid of the week, maybe theyll come in calm and ask if your medical. You can sit down with them and go over the paperwork and if it all seems reasonable they would rather walk away then make a big deal and have to waste time going to court knowing they'll loose because a jury wouldnt convict a collective growing together in a 10x20 space. With 500-600 plants they start to throw around words like marijuana enterprise.
Just be smart about this because its not about it being state legal its all about it being federally illegal. You dont want to go to Federal Prison. And to end my rant, if you get raided you loose it all... split it up cause ive lost it all and its not fun.