did a quick check also.....
it seems like there are no reviews found on Krizz on Renovation-Review.com also. However, in this website it stated that they are HDB-Registered.
Some companies maybe contractors instead of IDs, so you might like to check with them their portfolio and ask them some design-related questions to better access them.
http://www.renovation-review.com/contractor/krizz-interior-pte-ltd/
Their contact is
Telephone:
6297 7768