There are alot of variables. 25k may be doable if you contract it yourself and/or do that absolute minimum. Pool builders around here advertise under 25k regularly and it would possible in a perfect scenario that fits their exact spec of a 25k pool. That does not include much deck, screen enclosure, footers, removal of anything, fixing yard, only minimal equipment and a pool less than 12,000 gallons.
Your location has something do with it as well. Competition down here in FL is high and that probably helps. My build came to about 45k plus landscaping and I saved some money by self-contracting some of the subs. You can see my build in my signature.