Depending on site conditions ... it is always better to go with PVC vs some sort of Black Corrugated Pipe. Neither have anything to do with waterproofing. Not sure what the heck is spray sealing either. And only for $500?

There are different waterproofing methods: such as but not limited application of real waterproofing membrane (not $500), [and] installing dimple mat systems like Delta-ms [now too many vendors to cite], etc.

Prices vary regionally. Regions vary about every five miles.

BT and Mark. Thanks for responding. The itemized list is $3000 for the weeping tile drainage system (6'), which I believe is the dimple mat you're talking about and $500 to spray coat the interior basement walls underneath the dimple mat. Thus, the $3500. Thanks.

I guess I was completely off.

I thought that what common called a weeping tile is s a porous pipe used for underground water collection or discharge. https://en.wikipedia.org/wiki/Weeping_tile

Drain matts on the other hand is this https://www.dorken.com/en/our-products/products/residential/delta-drain.php

Apparently I am way off.

If I were you, I'd be spending my money for waterproofing on the exterior of the basement wall...where the water will be.

Thanks, we’re already sealing and putting an exterior drain system. We’re just adding layers of redundancy.

LOL We actually looked into Galveston construction and "basements" while there. This one looks low to me.

Always check conditions. Don't trust anyone with water or water proofing. Verify with the builder. Nothing worse than active leaks. One of my houses had double connected pits installed by us. For $50 the overflow was directed to pit two with the backup and a redundant drain. Pump2 would activate alarm alert when running.

I wonder if the OP has damp proofing mixed up with waterproofing. Two different things.

Virgil, I might have them mixed up, but I think we have that covered. We have a drain tile system on the exterior and interior of the wall and a sealant on the exterior foundation already. They just wanted to add another level of protection with the weeping tile drainage system on the interior on top of sealing the interior walls. I think that covers damp proofing and water proofing. This stuff is all new to me!

We have a drain tile system on the exterior and interior of the wall

I did that once when I realized there was running underground water just a few feet from the rear of the excavation. We also backfilled with river run gravel, as it holds water while it works its way to the drains which, at that time, were connected to the municipal storm sewer.

Interior foundation waterproofing systems can sometimes include a dehumidifier additionally. Interior basement waterproofing is sometimes more affordable than exterior waterproofing. In some cases, interior waterproofing is the individual probability because of there not being quite an area between successive door neighbor's house.

OP, can you describe the "waterproofing" applied to the exterior face of your basement wall?

If it's limited to spray on or rolled on material, chances are it's damp proofing, not waterproofing.

How serious is the underground water issue on your property?