Options for holding cash profit from sale of real estate

[Joan MacDonald]

Thinking of selling a residential duplex investment property in CT. A sale would yield $250-300k profit. Owned it for 5 years. I have a commercial mortgage on it in the name of my LLC that I also personally guarantee (as per the loan docs). That's the only debt on it. I'm the sole member of the LLC. I'd like to buy another property within a few years using the profit. What vehicle can I set up to hold this money so I avoid cap gains tax? I know that SDIRAs, etc take time to set up and that's fine. Just looking for what options there are given my details.

For context....
Net rental income on this property is $6500/mo. I have no retirement account. I have no W2 income. I operate a small nonprofit (an actual 501(c)(3)) in the education field. I have a 2nd LLC set up for other business income but haven't had income on that since 2020. I own my own house around the corner (also a duplex) and it's in my name (no LLC.)

My reasons for selling: 
A) prices are up,
B) my elderly parents need me and this house takes all of my time as a diy-er,
C) property management is 15% or more near me + it appears they only collect rent / execute leases; repairs would still require my energy, 
D) labor shortage means no reliable, skilled, sober handyperson to do upkeep that I do now (tile bathroom, paint a room, etc)
E) a cashout refi will not solve my problems- see B