...a heater core replacement at the very most, for someone who never has done anything meachanically, should take about 1 1/2 - 2 hours...by the time you bypass the heater core you already spent 1/2 hour...
...a lot of people would refer you to pick up a haynes manual or chiltons manual for about 19 dollars for any vehicle you own...say 54 bucks for your heater core and 5-10 bucks anti freeze at most...83 bucks total for your first repair...say another 17 for the nipple, total of 100 bucks thats quite a bit of savings..there is a wealth of information in those books and even more on here to show you how to do these simple repairs...
..as for the explorer's and rangers, 200k-250k miles is not unusual at all...my ranger is 160k and my explorer is about 190k...i paid 2300 for my ranger a little over year ago and i have been offered double that for it in the last couple months ...the repairs i did to it i was quoted the cheapest at 1500 bucks...it cost me 160 bucks in parts and i get a full write off on them and 1340 dollars never left my pocket....i am not a mechanic but i learned a long time ago the mathematics of vehicles...
...as for write off's on a new vehicle, it don't add up...you lose 3-5 thousand as soon as you drive it off the lot...then depreciate it over the few years you have it, add the interest of the loan and normal vehicle maintenance??? that can be very costly...
...trust me, if you don't want to work on your vehicle no problem...just be assured, if you do want to, there are plenty of people here that would be more than glad to give you some help when you are interested...btw, there is a used parts dealer on here who is incredible and there are alot of people here who wind up doing their own repairs after they find out it is not that hard and how much money they can save...that is only part of what this great forum is all about...