Used 4x4 questions

Hello,

I have searched through the thread a little bit and still have a few general questions to throw out.

I am the owner of a 2001 2wd 4cyl tacoma with 130,000. It has served me well but I am ready to step up to a 4wd. I will not be doing any real dedicated off roading but my wife and I are very active climbers and that means we are often on road trips and traveling on old roads which are in VERY nasty shape. We need 4wd and higher clearance than what our current tacoma offers. We hope this truck will last us a long time and we also don't want to buy one right as every part starts to wear out.

Our initial budget that we were looking at was $15,000 but a quick search shows that this does not go very far and we may need to adjust the budget to get what we want. So here is the question...

We are looking for a 2005 or newer Tacoma 4WD 6 cylinder, what milage range should we be looking in? Will we be putting in a lot of extra $$ if we buy a 175,000 vehicle?

Also considering the fact that we don't plan on doing any aggressive off roading would we be ok with a regular 4wd or should we try and get a TRD off road? I do not want to have to upgrade the truck after I realize that the stock setup is not good enough. I would rather put the money in upfront and get what I want

Thanks for all your help.
Eric