Opening Record Store

What is the $10K for? He's either trying to make rent if he owns the place or save from paying rent. If he's just trying to profit off of a cheap lease deal that he has, see what the real market rent is, and do a net present value calculation of the savings over the number of years at a rate of return of say 6% or whatever you can borrow money at (if you need it). That is all you should be paying if you want to be in that business, or I should say, hobby. There are lots of used record shops near me and covid has killed them.One also sells inexpensive turntables and sells a good amount of $4-500 ones to people just getting into or back into vinyl. I think on-line is the way to go, and if you rate good used ones properly, you should make money there. Brick and mortar, I doubt, especially if you need to hire an employees.

I had a record store in Albuquerque for 20 years. PM me at bowwowrecords on fb and I’ll be happy to help. 

I had a small (1,000 sq. Ft.) vintage store for 3 years - had 1,500 records in the store all classic rock unless I could find jazz.  All Vg+ or better and most NM or I didn’t sell them.  Over 2/3rd of them were priced at $6.00.  Could never/rarely realize Discog or eBay prices in the store.  In retail for my kind of shop we had to sell 3X our rent to make it somewhat worthwhile and a lot of profit went back into inventory.  We also took a hurting by albums being re-released a few years ago.    Not long before COVID my landlord decided to convert the space to daycare and terminated my lease.  I am so glad that happened to me.  Big record store in area recently closed after 4-5 years.  You could see cars in his parking lot diminish over time as novelty wore off.  10K$ in sales is a lot of records to sell to make that up.  And you are in California where life may never return to normal.  I’m in NJ and won’t reopen a business until/unless things normalize.  I’d have to be crazy.  For half of $10K I’ll sell you a storage unit with thousands of classic rock LPs with a retail worth of $30,000 plus.  

One abreviated word:

Don't.

You're going to compete with SalvArmy/Habitat sifters looking for THAT and happy to waste your time.  You'll spend most of your time listening to what You've bought to sort the trash from the 'ehh, OK's'.  

If it's not a 'labor of love' and a means to burn through $ you need to do so with, or perhaps running into the rare audiophile that admires your version of plucky insanity, don't...

Do you know how to run a business?  A real, honest-to-Whomever, retail business?  Incidentally, in a real niche market?  Hot for now, but...?

Suggestion:  Take a clue from the wizened ones here, blow off the B&M shop, and go online 1st.  Cheaper, you can stay home, work @ your 'leisure', and build/rebuild your/a market....

Get notoriuse....we have.  It's taken 13 years and rolling.

I don't sell audio 'anything'.

If that changes, I'd head online.  First.

(...and offer a 'Lifetime Warranty!'  As in, Mine. *LOL*)

Good luck, anyhow.  You'll need a lot of it..... ;)

I wish you well and all the best. I live in NYC and almost every single record store from Tower and J&R to Rebel Rebel and Rocks in Your Head are long gone :(  and we are worse for it. I don't know how you could pay your rent with such a low priced/ profit item... A larger space you could do a Starbucks cafe thing/listening room or booths  and maybe sell some turntables and used gear.
Some banks here are doing the Starbucks cafe/bank/ work space thing.
Anyway I wish you the best.
 I sorely miss browsing the racks of my favorite record shops...