1) Bulgarian citizenship can not be acquired on the base of small cash investment. There are strict provisions in the Bulgarian citizenship Act that require investment of serious amounts in the local economy, and specific terms to expire, before enabling applying.
2) Bulgarian citizenship can not be granted on the base of real estate purchase, even if done in the name of established local corporate entity. In particular cases and for particular foreign citizens (for example, EU residents) the purchase of Bulgarian immovable property could help obtaining long-term residence permit - but not for citizenship.
3) For a foreigner who cannot provide local financial securities, it won’t be possible to obtain a loan from local bank to finance the required investment before applying for citizenship on investment basis.
4) Bulgarian citizenship on investment basis cannot be obtained in weeks. Actually the local legislation establishes precise long-term periods of residing in Bulgaria, before applying for citizenship on investment basis. If anybody offers to you to issue to you Bulgarian passport in several weeks time, it is most likely a scam.
5) In relation to the above last words, there is no private quick procedure to apply for, and to obtain Bulgarian citizenship, instead of the long governmental path via submitting application at the Ministry of Justice, and the Bulgarian consulates abroad.
Well, if you don’t know the local regulations, the assistance in advance (prior applying) of local experienced Bulgarian lawyer is recommendable for advising on the possible option and for respectively for organizing the paperwork that accompanies. It is always better to spend 50-100 Euros for proper legal advice, than to lose instead thousands given to online scammers.
The above points do not represent particular legal advice for obtaining Bulgarian citizenship, but only have the role to help foreigners to clear their view, and to avoid misleading or false information or eventual suspicious offers for granting Bulgarian citizenship spread in Internet. Last year there have been reports on the local TV for anonymous overseas websites which offered Bulgarian citizenship against small tax and granting it in small terms, where journalists proved these were only scams, nothing else.