A pretty decent rule of thumb is that homes that are in subdivisions created in the last 15 years are subject to Mello Roos, or shall I say are in Mello Roos districts. It is not always the case but most of the time that will be correct. Mello Roos can add as much as .8% of the purchase price to your property taxes. Your base property tax rate (including other municipal bond fees and such) is about 1.1-1.15% depending on where you live in the county.
If you are looking at new homes simply ask the person in the sales office if the homes are subject to Mello Roos. If you are looking at homes of the quality of the Bridges it may be hard for you to find a subdivision that is not subject to Mello Roos. Buy an older home in RSF or Fairbanks or Solana Beach and those homes will not be subject to MR. Essentially the answer to the grandfather question I guess is yes. Either a home has MR or it does not. If a home was built before MR then it will never have MR. Awhile ago I posted a long post on MR fees in San Diego and had some links to it. You can google san diego mello roos and find really good resources. As you said you do have the option of paying all your MR fees up front when you purchase but that is a hefty buy in and I would advise not to do that and pay as you go. Well actually I have a big issue with MR so I would buy the older home and not pay but new homes are very attractive to people.
Hope this helped…oh yeah and again, any home generally over 15 years will not have MR fees with regards to your question about exempt.
