Jabiru and Rotax engines

I am doing some research into ultralight engines (planning to build one).

The Rotax 912S and the Jabiru 3300 are the models i am looking into.

Does anyone know how much it costs to maintain them? I just need very
generic examples to get an idea.

How much does it cost to overhaul them (one or the other)?

Any of you ever needed repairs done on them? Did you do them yourselves? How
much did it cost (wether or not did you do them yourselves)?

And how about oil changes, and replacements of parts?

Again, just general examples would be great for me to start getting an idea
of what I am getting into

Thanks a lot!!

--
Marco Rispoli - NJ, USA / PP-ASEL
My on-line aviation community - http://www.thepilotlounge.com