Hi,
You choice of technologies isn't correct. If you're serious with the project, take Wifi as primary transport and even don't play with Bluetooth limitations.
I don't know about Germany, but you may spend some hundreds of EUR, visit Kharkiv, Ukraine, play Laser tag and get amazing experience and ideas. It should save several thousands of EUR. If you want just to play for yourself - that's not a budget for the project. Real amount of investment should start from 5K.
Me and my team are oriented for professional wireless Bluetooth/WiFi/GPS solutions. If you're interested, please review existent solutions and their problems much technically. I would assist with professional consultations in hourly basis.
Kind regards,
Rostyslav Gryb