Head Gasket Replacement

Anything free is worth the price. If it's just the head gasket it's a pretty common fix. Do it yourself if you are capable or have a qualified mechanic do it for you. Labor would be the most expensive element since it takes time to dismantle all the "stuff" on top of the engine, the gasket itself is relatively inexpensive. Any good shop will give you an estimate. A Toyota stealer will probably be the most expensive.

Just need to realize that it would be "extremely" rare to only do the headgasket. Does the engine smoke a bit? Maybe the head should be gone over by a mechanic regarding valve sealing, oil seals, flatness check, etc. Everything involving the timing belt (with tensioners/idlers, cam and crank oil seals, water pump, oil pump, etc.) is there and it may be time for that. What condition is the turbo in? Valve cover gasket and spark plug tube gaskets. Spark plugs, distributor cap & rotor, spark plug wires, distributor o-ring (oil seals). Many hoses become accessible with the turbo removed - they get baked by the heat of the turbo & engine - maybe hose are hard/cracked and need replacement. Intake & exhaust manifold gaskets and other gaskets associated with the intake & exhaust systems. I can go on, but you get the idea. Some must be replaced - others it is a choice (pay me now or pay me later). Up to the owner on what is best.

Don't take this wrong please. I'm all for preventative maintenance but also of the "if it ain't broke, don't fix it". Replace the head gasket and related pieces. Easy to go down a rabbit hole and start throwing money at something that may or may not need to be fixed.

I agree with you, Sea-J. What I'm trying to say is that, maybe the previous timing belt change was 50k or more miles ago - would you put it all back together knowing you should be tearing it all apart 10k miles down the road? And some items like hoses may break because of age and require replacement. I'm just trying to paint a picture that on these All-Tracs, one needs to be prepared when going into something like a headgasket replacement. I've gone through two 5th Gen Celica All-Tracs with maintenance needs - just sharing my learning.

Yup. When I replaced my timing belt last year the tensioner, oil pump and water pump were replaced also. Some are actually sold as kits.