I need an excel spreadsheet for property development appraisal for lots of variables

Description of excel work: Hi- I need an excel spreadsheet to be made with lots of variables (around 80 total, not all would be used for each site) to be able to quickly and accurately appraise lots of property and land development opportunities.

We're a property development company and we look at lots of different potential sites and properties that we need to do appraisals on. Each site would have different data entries, we would be looking to achieve different things with the sites and would use several different methods to purchase the sites, so there are lots of different sets of variables. We want a spreadsheet to be made to include lots of different factors and cost variables, and for the spreadsheet to have lots of different pages, or ideally, a means where we can assess several variables, i.e. different purchase prices, or renting the site instead of purchasing, next to each other on the same page, so that we can compare all options. Our aim is to be able to see very quickly on entering the data whether a site would work for development or not. Please let me know if you have done something like this before and what the cost would be. Any feedback you have or ideas on how to create a better spreadsheet/better variables would be much appreciated!

I don't want merely a spreadsheet where all data is combined together, I want an active working tool whereby I can input all data and edit all variables, and analyse the results and numbers from all variables, and then to be able to save and see the different results from the different variables alongside each other to be able to compare the best way of dealing with each site and to see whether to progress with the site or not. I want it to be presented smartly so that we can show the spreadsheet with all calculations to investors, preferably with our company name and logo at the top.

The end result is, I want to be able to see clearly what all the total costs from all sectors are- so purchase, planning, development, sales etc, to see the total cost, but also to be able to work backwards to see once we've worked out all the costs against the total value, what we could offer for a site, according to different purchase models. I've got a list of about 80 variables/costs that would need to be included. I want the spreadsheet to serve as an appraisal calculator we can use over and over again and to present to people.

Please let me know if you are able to do this and have worked on something similar before. thanks.
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