Selling home: buy again or wait?

Hi. I am selling my home just outside the GTA and moving away to a university town for 2-3 years. My kid is going there and we want to stay together as a family. End goal is to land back in the GTA.

What should I do with the profits of the home sale?

Some options I can think of:

1. Sell now -> Buy in the uni town

Upside: I keep a stable primary residence.

Cons: the home is not likely to appreciate given current market trends. Any equity built paying $ toward principal would get lost in selling costs/ depreciation.

2. Sell now -> Rent in the uni town -> Invest -> Buy

Upside: invest profits into our TFSA's. Possible 8+% annual return tax-free. Gives me the time and flexibility to re-enter GTA if the market drops further.

Downside: stock market crash could wipe out my investment and I could get priced out of the GTA market

3. Rent current home -> Rent in uni town

Upside: I still have the home and it continues to build equity

Downside: I would take a $200-300 monthly loss (which I can hold). I do not have flexibility to move back in whenever I want. Costs to rehab the home after tenants leave offset. Landlord stress.

My question is- what are the "rules" here?

- Agents will say if you sell, then buy right away (stay in the market).

- My boomer dad saya to protect the primary residence and don't pay someone else's mortgage

- My HNW investor friends say I can grow it lots of % if played right

Other factors:

- bought current home in 2020 and if I sell now I can still get some profit

- we love the home but have no attachments to it. We want to end up closer to the GTA

Is there some kind of "wealth building ladder" or playbook that says paying off the primary residence is the topmost priority? Or that anyone who tries this maneuver (self & invest & buyback later) is destined to fail?