Setting up mortgage payments

[Derek Atkins]

Hi,

prl <prl at ozemail.com.au> writes:

> I'm not sure what others were talking about, but I wasn't talking
> about problems setting up mortgage schedule payments. The minimum
> payments I can make on my mortgage are fixed, and at intervals that
> GnuCash can work with, so that bit works very nicely in GnuCash. I
> make advance payments at irregular times that suit me, and they're
> entered as manual transactions.
>
> What I can't do with any useful level of convenience is calculate the
> interest that should be debited at the end of each month. That's my
> main variable, and its calculation is complicated by all the factors I
> mentioned in my earlier email.

This IS what I am talking about..  GnuCash's mortgage & loan druid,
using the SX features, *can* compute the principal/interest splits in
certain, limited situations.  However it cannot handle pre-payment of
principal (it would need balance-as-of-date to implement that).  And it
cannot handle interest rates that change unpredictably.

While a balance-as-of-date function could easily be integrated in with
existing infrastructure (modulo the UI), dealing with arbitrary interest
changes would be harder because you'd need to keep track of potentially
multiple rates during a period.  The data structures are not designed
for that.

[snip]
> I think that Derek has misread what I've written about variations of
> my interest rate, though. My interest rate can change on any day, but
> it doesn't really "potentially change every day". It's changed twice
> in the ~six months since the start of the mortgage. The first change
> was on the 15th of the month, the second on 24th of the month. Both
> downwards :)

Nope, I didn't misread you.  I just took what you said to it's logical
generalization -- the interest rate *could* change arbitrarily on any
date.  It probably wont, but it *could*.

-derek

-- 
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
       warlord at MIT.EDU                        PGP key available