Exchange ideas here and there. 

Yes you can raise money for deals and you put in the sweat equity in exchange for cash.

I exchanged information with them and would stop by their projects for the next month to see their progress.

You can't compete against the all-inclusives unless you offer complimentary food and booze or you're cheap, as you seem to be confirming.This being said:1) Properties in Mexico/Cancun trade in USD so you have no foreign exchange risk in Mexico while properties in Colombia are traded in COP, the Colombian peso, which has been tanking over the years, eliminating any hope for capital gains for American investors.2) You can get a mortgage in Mexico but you can't in Colombia so even with lower revenue, Cancun would likely still be more profitable, even if you don't take capital gains into account.3) The political risk is much higher in Colombia, especially at this present time.Is Cartagena a bad investment?

If you’re comfortable with the tenant risk and low cash flow in exchange for a solid property in good condition with long-term appreciation potential, then proceeding could make sense, maybe you you can negotiate some concessions?  

I have a few properties in Durham which I obtained as a 1031 in 2022 or so, and they are currently not really cash flowing.

OrchardOrchard allows you to exchange the current equity in your home for the purchase of a new home, and then selling your old home after the purchase.

Hoping To exchange some connection and also business together.

Knowing this information, should I sell and take 300k(ish) to a bigger multifamily or apartment via 1031 exchange?

If you don't want to long-distance landlord and find it to be a pain, then sell it, 1031 exchange it or owner finance, like you mentioned.