Development feasibility analysis

[Account Closed]

I have been acquiring a contiguous group of properties that I am now ready to develop. RE is a part-time activity for me and I am relatively inexperienced. It is a low risk project and I am not very leveraged, so I will have no problem completing the development. Recently, however, someone asked me if I would sell the project so they could develop it. The site is four hours away from me, so it is tempting to sell and start a new project closer to home. 

I would like to assess this project through the eyes of a developer so I can determine a reasonable valuation. I am also considering co-developing the site, so I would like to assess that scenario, as well. 

I have some nice acquisition analysis spreadsheets, but nothing specific to development. I am looking for software that a real developer would use to assess the feasibility of a development project--something free. Briefly, the properties are valued at about $1M, based on NOI. Investing $150k and leasing a restaurant will increase the value to about $2M at EOY2. An additional $1M investment will increase the value to about $3.5M.

I would like to have software that will allow me to phase-in development costs; account for loans at EOY1 and EOY2; account for lease-up time; assess different scenarios; etc. I would also like to assess the pros and cons of c-developing the site.

I appreciate your help.