I decided to post links and codes that some people might find useful, because I sometimes do search for such things on the internet.
Referral bonus code for Bondora (get 5 EUR): https://bondora.com/ref/BOA94131
Referral bonus code for Mintos (+0,75% on all investments): PEIR4W
Referral bonus link for Estateguru (+0,5% on all investments): https://estateguru.co/en/investor-referral/?switch=en&userPromotionCode=EGU2
COS discount promo code link (15% off):