How to improve Laser reflectivity at angles

Hi everybody!
Im working with a Polytec LDV (OFV 505) and I need a good reflection when the laser is incident on a surface at an angle. Is there anything like in a powder form that can improve the reflectivity at angles.
There is one product which goes by the name Developer BEA (www.diffutherm.de) which is an aerosol available in Germany. Is there any similar product in USA?
I tried reflective tape and reflective paint and it was satisfactory, but what Im looking for is something that I can apply to the surface and then wipe out easily when done.
Please help me.

There is a white paint designed specifically to go on the inside of integrating spheres; I believe it is bismuth-based. But it is terribly expen$ive, and it will not simply wipe away when you're finished using it (eg. it is permanent, not temporary).