I was able to catch my cylinder heads when they were warped but bot cracked. Replacing the cracked cylinder heads can be close to a $2,000 job. But if you ask me and the Jeep is in good condition with no rust issues then I believe it is worth having the work done. Considering the cost of a used vehicle and making payments especially if your retired or on lower income as we are, I put close to $6,000.00 into everything from engine, A/C, Fuel Pump, new tires, ABS repairs, emission hose replacements and 4x4 transmission front and rear seals not to mention miscellaneous coolant system, radiator, charcoal filter canister and miscellaneous sensors - since 2014 and it was all worth the cost. I could not find a used 4x4 for that low a price and my mechanic warranties his work for a year. Remember, mine was a 97 and I'm partial to the older Mopar engines.
If the heads are warped the price is closer to $1000 to repair. So before you do more damage you shoild start looking for mechanics who will work with you if your willing to spend the time online locating the parts that are needed. Even if the heads are only warped, they need to be removed and sent out to a shop that will flatten them and clean them up, checking to see if there are and cracks beginning to format that you might not necessarily see without (I think it is called) a magnaflux non-destructive magnetic testing inspection that can identify a subsurface weakness forming that weakens the metal alloys just prior to a crack forming.
Anybody else hade a good suggestion to help him save some money. One other thing that can ease the pain but has much to do with your credit rating. I worked dawn hard to determine my credit scores in the good and excellent category. I was able to get a couple of cards that I started using sine retiring on Social Security. I pay them off each month to get anywhere from 1.5% to 5% back on purchases and if paying off before the interest starts it helps with the monthly budget. Most of the new cards come with a one to two year zero interest rate as long as you pay the balance off within the no interest period. You have to be careful with these because your credit rating will from fast if you exceed 30% of the card limit. For something heavy like an auto repair you will most likely be penalized once you put the repair on the card. Also, you take a hit each time you apply for credit and they run a hard credit check on you. If you have equity in your home, you can try for a home improvement or credit consolidation loan. You might take a hit for this but the mostly interest rates are very low - much lower than the 23% to 29% annual interest rates on credit cards.
So it boils down to 1) is your Jeep in good enough shape to invest in replacements of a cracked cylinder head and 2) how much more life can you expect to gain one all the repairs needed are completed?
Good luck to you.