Thanks William for your comment.
I personally think a monthly cashflow forecast over 3-5 years is likely to suggest more precision than is reality given the volatility of utility and other costs.
Our thinking is developing along the lines of top-line 5 year annual forecast for revenues (fairly predictable) and overall costs along with estimates for likely potential major project costs (eg new roof) to get a sense of how much financial flexibility as an Almshouse we have and to generate an estimate of how much we should set aside in sinking funds for specific projects.