If the condos were completed, it is likely that the condo docs, and the association information, is available at the registry (and may be available on-line). But in most small associations, the association is the owners. The main concern here is who is paying the fees, and how many fees will be necessary in the future. With new owners en route, and no idea where the budget is (in fact, the budget may be zero), it could be possible that the capital reserve fund for these units is empty. This would be bad, especially if there are looming expenses. I would suggest getting some experienced help here, or you could get whacked with an assessment of considerable size. Foreclosures come with a lot of risk, and there is definitely risk in this situation. Furthermore, be forewarned that you may not be able to get a mortgage if the other units are bank owned, so check with your underwriter pronto!
Also, you may have to front the money (lent to the association) for insurance and pay all the common expenses yourself. You should be able to get paid back when the other units are sold. Keep careful records and establish a budget which saves enough money to purchase insurance when it renews, plus water bills, common electric, landscaping, snow shoveling etc... The banks who own the foreclosed units are 100% responsible for reasonable condo fees.
The common areas do come under the master policy.
In addition to giving you a major headache, did we all manage to answer your questions?