You don't need huge marketing budgets. It's my theory that the better the product the less marketing you need. Let me give you an example, my brother developed a 'software synthesizer' (a 'VST') which is used to make electronic music. His particular VST became extremely successful, if you turn on the radio and hear electronic music, there's more than 50% chance the producer used his product. He never spent even a dime on marketing ! I remember when nobody even knew about his product, we talked on how to get it out the public. I suggested to just start googling other VST's. We quickly found out which were the most influential VST magazines/reviewers/websites out there and mailed them versions of the software to review. Then the ball started rolling itself, those magazines started raving how great his software was, most gave 10/10 ratings and quickly more and more people started using it and now almost every DJ/producer out there uses his software. Again, he didn't even spent a dime on marketing.
So in other words: if a product is really good, it will most likely just sell itself. You just need to send it out the most influential reviewers and if they think it's a great product, they'll write a great review and that's how you can get famous without even spending a dime on marketing.
So, I suggest to actually do the same. Find out which websites/magazines are the most influential. A good way to start is to see which websites are quoting articles from which websites. If you take for example vrnerds.de, they usually quote from sources like roadtovr.com or vrfocus.com, so those are the guys you will want to have to review your product.
Also it might be an idea to just have some people here try it, I'm sure they'll have good feedback for you about what they like and what they don't like. Maybe talk to a few users, you could maybe make a deal where somebody first pays you the $900, then gets a prototype to play around with for a week sends it back and then receives the final product when it's ready, something like that could work I guess. Again, I think it's all about getting to a really good product because if you get to that, you will get great professional reviews and then it will most likely sell itself with minimal marketing effort.
Anyway, just my 2 cents.