Hellzero

@BillyBass You forgot one very important point : 4) Go to a real luthier who is also a bass player (there are some) and get your bass totally set up to your taste while staying there when he is doing the work. And don't forget that the strings have also a great impact on the sound. Come with your amp too. You have excellent pickups on your bass, so the "issue" certainly is the perfect setup. Sometimes it takes me 2 to 3 hours to have a perfect setup on a bass and I've set up thousands...

A fretted Fender Tony Franklin signature model will also be perfect just like any very good sounding P-Bass with an added Jazz Bass pickup in the bridge position, which is a typical 80's mod. Avoid the expensive Yamaha BB2024X that sound really dull, especially compared to an old Yamaha TRB-4P...

An old Yamaha TRB-4P will tick all the boxes.

According to WD Music, this one is exactly the same : https://www.wdmusic.com/wd-custom-pickguard-for-fender-american-deluxe-21-fret-jazz-bass-details.html

Here is your answer. So you'll spare some money for a physiotherapist or an osteopath. 😉

Does it justify the delirious asking price ?

You can also do it the Fender way and spray the frets too. Then make a frets dressing... They made it this way at least during 4 decades without anyone ever complaining.

Sorry @Happy Jack it's tuned in D.

This was recorded with a cheaper than chips amp through my smartphone... Le Fay Remington Steele 6 RHT CC CAP Big Block.mp4 This is the amp : https://m.thomann.de/gb/joyo_ma_10b_portable_bass_amp.htm Strangely, it sounds amazing at, of course, low level. I also bought this to use if off the mains, but it can also work on batteries : https://m.thomann.de/gb/harley_benton_powerplant_powerbank.htm

This :

I found it next to your toilet, or was it in the Bongo case...

Even better...

Send me back my money !

Storing is one thing, you have plenty of more or less coherent explanations on how to do it the safest way. If your storing place is dry and the instrument is not subject to any fast temperature and humidity changes, than it will be safe. The problem you don't mention is getting them back into your renovated house. I read that you'll have to make some plastering which means water and maybe a lot of water (you'll be amazed by the huge quantity you'll use). If you get your instruments back into the house with a permanent high humidity, get ready for some huge problems. Buy a hygrometer for your storage place and one for your house as a good storage humidity rate is around 45 to 55 %. And please store your instruments tuned with the correct tension on the trussrod as it's wood and it's the way it's intended to be used or get ready for some twisted necks and scratchy pots... Another solution is simply to sell your gear and buy something "new" when the renovation is over as you wrote that they are not high value instruments.

And the 6 strings model has 7 strings too. Glue, definitely !

I should have kept mine...

I'm no tiger, I'm a lion.

I'll take the stools.

Get some paracetamol on hand. 😉

They did, I owned a few and @itu has an original one.

Is the neck really well tightened as a not firmly screwed (and maybe screwed up too 🙃 ) neck acts as a dampener. And a too soft body will act the same way. If there's a shim, check that it's made out of hard material. Otherwise @chris_b is right and just sell it. Bad instruments do exist and by Fender it's even a kind of epitome. The good ones are quite rare simply linked to the fact that they assemble parts without caring if they really fit together and just sell the whole as an instrument, not giving a sh*t if it's good or bad : they just have to make profit. Harsh for some, but it's the plain truth. The funny thing is that I'm still looking for a very good sounding P-Bass after more than 30 years : there's always something wrong and I've played a lot and owned a lot too...

@StickyDBRmf : and the monorail bridge patent belongs to Rolf Spuler too just like the D-Tuner for it. Thanks @LeftyJ

Here are my two original Ibanez AFR from 1991, designed by the late Rolf Spuler, a true luthier and genius. These are certainly the most beautiful and ergonomic basses ever made. Are you sure you know the definition of ugly ?