I've been considering home ownership, and all other things equal, I'd like to know how much of a mortgage I can afford based on the rent I currently pay.
Not including heat and hot water, I pay roughly $800 a month on a two-bedroom apartment. Most mortgage calculators take the total mortgage you get and calculate how much you'd need to pay per month to get that mortgage - I'd like to take my current monthly payment and find out what the highest rated mortgage is that I could get.
Ideally, I'd like a formula I can adjust - for X monthly payments, over Y years, at Z interest and tax. That way, I can adjust it for any additional budgetary concerns (insurance comes to mind).
So, for $800 a month, over a period of 30 years, at 3.5% interest and tax rates, with 20% down, how big a mortgage can I take out?