The surface appears to be approximately 15 to 25 years old. It does appear to have significant calcium and or mottling present almost on the entire surface more concentrations seen in spa. I would honestly expect that a lot of this could be removed with draining and light acid washing to expose a more uniform pattern present except that the surface is older and if the acid is too strong it may greatly reduce the remaining life of the pebble surface therefore it may not be recommended to do an acid wash but rather water treatments overtime. You may start with doing the spa since repairs need to be made on the spillover and judge how well the light acid washing results show still to drain and acid wash this pool correctly would likely cost around $1500 to do it correctly and professionally to do just the spa it might be a $650 job. Also know that it does appear that the plaster is delaminating in the spa potentially but most likely at least a 95% chance and if that is the case then the spa itself will likely need to be plastered soon at the cost of around $3000 the plastering should be done around the same time as the tile repair that should be performed to avoid duplicating efforts. The tile repairs will be described in the tile section. Also note that throughout the spa and pool there appears to be penny sized rust stains. They do appear to be surface only related but that should only be confirmed when treatments and/or service is performed note that the same size and quantity is roughly found in the pool & spa leading me to believe that it again it is more of a surface stain if I had to guess a penny or several pennies were thrown in maybe in an attempt to help kill algae that may have been present. There are several spots in the pool too many to count and there are likely less than 20 in the spa. The pool surface was more difficult to see due to the windy conditions and it being in the shade but they did not appear to be any issues present in the pool like delaminating like we are seeing in the spa which leads me to believe that the pool likely has some more remaining life potentially up to 10 years assuming water loss is not seen again judging by the water chemistry results we are seeing some signs of water loss being present but again not confirmed recommend retesting water chemistry in 1 to 30 days to confirm.
Estimated cost grouping: Spa acid wash $650 or full pool $1500 plus spa plaster $3000 plus rust stain confirmation/treatments ($500+).

The waterline tile appears to have all its mortar present. It does have considerable calcium buildup presence that could likely be removed for approx $655. Because of the water jets present there is a considerable amount of calcium present located mostly near the deck jets. Also the spa spillover into the pool has some issues cracking movement. This area will need to be repaired and re-waterproofed at a cost of $1000 to $2000.
Estimated cost grouping: Calcium removal $655 plus spillover repair $1000-2000.

The pH and alkalinity are very high likely above 8.2 pH and likely above 120 alkalinity. It does appear that the calcium hardness level is slightly elevated but the signer acid level appears to be closer to 200 indicating that there is a potential for water loss in this pool but not definitive because the calcium hardness level is higher. The chlorine levels are very very high it is likely hiding an algae outbreak therefore I would recommend balancing the chemistry to the appropriate levels which would be around $150 and then potentially treating for algae if present for less than $150.
Estimated cost grouping: Chemistry balancing $150 plus algae treatment less than $150.

There are two main drain covers in the pool and there are two in the spa. It does appear that all four will need to be updated for safety at a cost of around $200 each. Note that it would be wise to consider upgrading the main drain in the spa instead at time of re-plastering to install a VGB compliant cover instead of upgrading these covers at the cost of around $1000 instead.
Estimated cost grouping: Main drain covers $800 or spa main drain upgrade $1000 at re-plaster.

The bottom cleaner will need some minor updates on the tires likely a new hose complete including all adapter and a new tail soon less than $205.

Running fill, generally a sign of water loss, recommend service to update this float and confirm status ($125-250+)

There are two halogen color changing lights in the pool both appear to have condensation inside the light lens which is expected for its age over 20 years old. Both light cans will need to be replaced. The options will be between $200-$1250 each depending on quality plus $400 labor each to install and there are two lights both need to be updated.
Estimated cost grouping: 2 light cans $400-2500 plus labor $800.

The spa light is a smaller 6 inch light. It also is nearly dead with failing output and condensation present. Recommend updating at a cost of $200 up to $1150 for the light can depending on quality and then $400 labor extra.

The filter is original. It is a 400 square-foot filter. It is likely due for service now at $150 to confirm if the filter element inside is due for updating which is very much likely is at a cost of around $700 plus a tank O-ring set would be wise to update at less than $200 and a new liquid filled pressure gauge would be wise to update as well. Note that elements are due to be replaced every 2 to 5 years and therefore this one is likely due to be updated now.
Estimated cost grouping: Filter service $150 plus elements $700 plus O-ring $200 plus pressure gauge $50.

Overall ideal , recommend minor service and safety updates = new bonding , and lid o ring / service. Otherwise ideal.

The spa jet pump (initially thought to be the water fall pump) appears to be leaking and somehow connected to the plumbing underground that we cannot see. It is likely there is an additional issue here that will need to be investigated in order to get this particular pump working still because this pump is leaking so profusely it is likely that the pump itself will need to be updated especially the wet end like we had a cost of around $1200 up to $1800 for the pump and around $800 to install versus repair which I do not feel this pump is likely repairable but if it was a new wet end and seals would likely run less than $1000 installed also it appears that it needs a check valve installed at around $500.
Estimated cost grouping: Check valve $500 plus wet end repair less than $1000 or new pump $1200-1800 + $800 install.

It is a miracle this heater is functioning. I did turn it on at 76° and it has heated up to 91° in approximately 20 minutes again. This is a miracle. This heater has been heavily abused by the salt cell and high chlorine for prolonged periods of time it is possible that this has been serviced and that is why it’s able to still function but I would not anticipate this working longer than another 1 to 24 months or less. The cost of a new heater is less than $5000 for a 400,000 BTU heater and installation is around $1000.

Estimated cost grouping: New heater $5000 + $1000 install.

The equipment panel is an intact touch top-of-the-line system in working order. The only issue I see is to update the breaker to GFCI on the plug and adding one for the pool lights as well for a cost of less than $100 and electrician charge of around $300.
Estimated cost grouping: GFCI breakers $100 plus electrician $300.

The salt control system appears to be functioning but it does appear that it is throwing an error on the salt cell itself which is indicating that the salt cell is due to be updated at a cost of around $1000 now. Because of the age of this controller I am only 20% confident that the panel controller itself may be due to be updated or replaced and if so that is a cost of around $1000 as well but it is likely that it is only the salt cell that needs to be updated.
Estimated cost grouping: Salt cell $1000 or controller $1000.

The pool equipment pad has heavy sun exposure likely between 20 to 25 years of heavy overhead sun exposure removing at least more than 50% of the black paint that was applied to it. First I would recommend repainting and relabeling this entire equipment pad but after service workers performed at a cost of around $300 and then applying UV Mesh over this entire equipment pad to help prolong the equipment life at around a cost of around $50. There are several leaks present which is to be expected. One is on the pool or spa three-way valve and the other appears to potentially be relieving to the other three-way valve for the pool returns. Still three three-way valves are due to be updated via service at minimum O-ring service at around $100 each times three but likely the guts will need to be updated at a cost of around $200 each. On top of that the salt cell should be removed and a salt cell spacer installed at around $50 in the meantime and a check valve should be installed on the return of the spa heater if desiring to add a new heater in the future at a cost of around $500 and also recommend adding a heater bypass at a cost of around $900 optional not required. Recommend updating the hose bib for less than $50 and recommend updating to hard plumbing on the booster pump to help prolong the pumps life at a cost of around $500.
Estimated cost grouping: Repaint/relabel $300 plus UV mesh $50 plus three-way valves $300-600 plus salt cell spacer $50 plus check valve $500 plus heater bypass $900 optional plus hose bib $50 plus booster hard plumbing $500.