[consulting] Billing Increments

[Larry Garfield]

On Sunday 10 January 2010 01:45:35 pm Fred Jones wrote:
> > Do a quick search for "context switching time" or "productivity
> > switching" and you'll see numbers from 5 mins to 45 mins to actually
> > recover from a distraction and get back into a zone of productivity. I
> > think the common wisdom is at least 15mins.
> 
> Very interesting results I found--many people have written about the
> pitfalls of multi-tasking.

There are many.  Probably more than you just found. :-)  It's not just multi-
tasking, though, but any interruption.  A computer's context switch time is 
maybe 400 CPU instructions, a fixed number, plus CPU cache rebuild time.  A 
human's context switch time is several minutes (varies with the person), plus 
cache rebuild time (the time to get "back in the zone"), plus "wait, did I 
forget something else?" time, which goes up the more interrupts you have.  So 
the more interrupts you have, the more expensive each one becomes.  That 
includes random coworkers asking you about something, too, not just clients 
asking you to bill them on something.  And let's not even start on IRC and IM 
and such, which are a disruptive interrupt hose...  (Useful at times, 
absolutely, but also a massive hose of interrupts.)

> Repeat that every day (for one crazy client) or once a week for some
> clients. Then at the end of the month I see if the time is worth
> billing--if it's small, I just roll it over until next month and
> eventually it's enough to bill. I have a bunch of clients like
> this--some every other day and some once a month, they have a little
> request.
> 
> But I do agree that it must reduce my productivity, that's why I was
> thinking about billing each day's work as 15 min. instead of 6
> minutes. That makes up for my loss. That's what I was thinking anyhow.
> 
> Fred

A 15 minute minimum for even thinking about a given client is quite common.  
Some professions pro-rate to an hour, but I think that's excessive.

Another possible option for some clients is a standing support contact.  
$X/month for "all that random little crap".  They get a flat number they pay, 
and you spend less time tracking how long it takes to correct a spelling error 
(and you know a minimum amount you'll get from them as well).  For anything 
bigger (for some definition of bigger you negotiate with them) you actually 
give them an estimate and let them approve it as a "real" task, which you then 
bill at whatever your hourly rate is.

If a fair portion of your business with that client is that sort of low-level 
noise, it's probably easier for you and them to just have a standing 
"$100/month gets you up to 50 minor tweaks" agreement.  It's less overhead and 
more predictable cash flow for both of you

--Larry Garfield