What are the main warning signs in a Buddhist centre? I have been to different temples/centers/monasteries from different schools, most of them I would return regularly, but in a few I found things that didn't agree with some personal views. I must say 100% of the time I found people with nothing but good intentions, but not always I agreed with the methodology, practices or some core believes, for example: Having a "cult style".

That said, I would like to ask: What are the main "warning signs" (if any) we should look for when going to a temple for the first time? (I'm not talking about a simple visit, but Dhamma talks, classes and meditation).

This question aims to help beginners, it is very hard to identify "unusual practices" when a person is just starting with Buddhism and have no idea what is Vinaya or the Suttas for example.
Best is to do some reading of the main Suttas, such as: Anapanasati Sutta, Maha Satipatthana Sutta and see if what the center in question teaches corresponds with the Suttas.

Also see if the operations / techniques adhere to this:


Should ideally be run by donations and not by charging a fee
Should not be cultish
Should allow free thought and inquiry 
Should not have practices which harm oneself or make oneself agitated or do the same for others


The last point you can only know when you have practiced the techniques taught at the place and found out you are are at peace and also cordial with others. Now if you do find a lack of peace and cordiality, it may be there is something wrong with how or what you practice. However, you should then take care -- and it is easy to misjudge this -- that you are indeed following their instructions. If you do that, and rule out the possibility that you haven't followed their instructions (in which case, maybe you're just doing your own thing and that is the problem), then there is a good chance there is something wrong with what you have been taught at the particular center.

Sometimes certain traditions may not encourage practices outside the tradition (including reading). In that case you have to look at the motivation behind it. Is it trying to have a grip or hold over the person? Or is it concern that undesired results may be brought about by mixing different techniques? Or is it concern about not being able to handle dangerous results of an unfamiliar technique? Many traditions are geared towards preserving the techniques exactly as handed down through generations and due to this, variation may hamper the results/benefits. This is why you have to be very careful and try to look at it without prejudice.