Buildability assessment is an important aspect of real estate investment, as occasioned by the high cost of land and building materials. This study examined the influence of buildability assessment at design phase in real estate investment in Port Harcourt, Nigeria; to determine and minimize wasted effort before real estate investment commencement. This study adopted descriptive survey with a total number of 340 well-structured questionnaires distributed to clients, contractors and professionals; out of which 221 were retrieved representing 65% response rate. Data collected was analysed using descriptive and inferential statistical tools to determine the effect of buildability assessment on real estate investment. The major factors responsible for failure of buildability assessment are resistance of client to buildability programme, incorrect and inadequate design detailing, errors, omission, under/ over design, incorrect specification of materials, construction difficulties, non-optimum materials usage, simple installation, nature of soil etc. as shown in the findings. Unstable economic environment, width of the investment, finance for real property investment, land tenure legislation and land administration, socio-political issues, real property data banking, provision of physical infrastructure and inflation rate were identified as the reasons for the buildability assessment on real property investment. Furthermore, consequences of absence of buildability assessment on real property investment include: delay in property delivery, reduced investment life-span, wastage of invested capital and loss of capital, conflict among lease and lessor, real property investment on long void period, increase in maintenance and repair, loss of investment income, discouragement of prospective investors, difficulty in real property investment and unhealthy investment procedures. Therefore, it thus reaffirmed the relationship between buildability assessment and real property investment as statistically significant with F (0.659) =12.74; P