It is a very tricky balancing act for us.  The last county we added was over a year ago, and in addition to the 20 minute drive there is a $5 bridge toll (Marin County California).  Initially we talked to our clients to make sure we had work there and then crunched the numbers to make sure that we could at least break even.  In some cases the client allowed us to add a bridge toll, but in morst cases our clients wouldn't tollerate any "travel realated" charges.

What we have found is that in most of the more 'out of the way' counties (if you can call any location in the San Fran Bay area out of the way) clients are already accustomed to paying more.  Even abstractors that live locally in Marin charge more money due to their lower volume allowing us to price comparably and still make enough to cover milage.

The most difficult part is determining profitability - time, milage & staffing vs. payment.  In some cases we have tried (unsuccesfully) to develop correspondent relationships in the more rural counties - in all those cases we ended up simply refering our clients to the local abstractor.

I also wrestle with ethical concerns.  Any time we step into a new county we are taking work away from someone else.  We always work to be competetive and not devious and I try not to think of the new business we get as stealing food out of someone elses mouth.

This probably isn't very helpful ... sorry & good luck!