A good rule of thumb that can be used in the Singapore context
Office Space – 75-100 PSF
General Lab 100-150 PSF
Wet Lab 150-200 psf
Chemical lab 150-200 psf
GMP lab 250-350 psf
Cleanroom 500-600 psf
This would include basic fit out and not equipment. every building is different, with different levels of fit out and services; therefore it still makes sense to perform feasibility studies with respect to a site or multiple sites.
For example, some buildings might have floor, ceiling and ACMV fitted, others might be a blanks canvas even needed.