A few suggestions, take what you want from them.
The most climactic period of the drug wars in Colombia were the mid-eighties through to the early '90s. That's yer classic Medellin cartel, Cali Cartel period. El Patron, the bombings etc and also the most active period for the yanquis as well. Fear not, plenty of big porn moustaches. In fact, there still are to this day. I know this is 'loosely based on' ( a bit like Narcos) Colombia but Colombia in the late eighties is a good start point.
The Colombian Army at the time was wielding G-3s and mostly wore a leopard spot camo, in the nineties they moved into US woodland uniforms and started sporting Galils. That said they received a shit load of US weapons, M16s, M60s etc and the SF and elite intervention and anti-narcotics brigades tended to use M16s. Of course a scenario 'based on..' means you could use anything Western. Outside of Peru and contemporary Venezuela, you won't find any Eastern bloc weapons in use by the security forces. The national police would tend to OG uniforms and favoured an odd sort of bush hat with one side pinned up.
The TAG Vietnam range Special Forces would be a good choice. Another option might be Parkfield but on the whole, they weren't wearing tin hats in anti-narco ops. I've backdated Eureka's USMC Force Recon with some weapon swaps so they are another option. The old Wargames Factory survivor sets are great sources for the spares box.
If you want G-3s then you could use Bundeswehr as proxies but probably a better option would be the Eureka Portuguese with head swaps.
Eureka's African ranges are also a good source for narcos. Loads of civvy/ semi civvy clad types wielding AK-47s and Eureka's moderns are simply the best sculpts available, a world removed from the others. By the by, there are significant populations of Afro-descendent in South America. Colombia has a large Afro-Colombian population, especially in the coastal regions. Fortunately, the features are so subtle they paint up as non-Africans.
Your country, your rules but remember that Colombia, like the other cocaine producing nations is Andean. So the popular trope of palm trees and the tropics is a bit off. Medellin, which is a wonderful city to visit, is known as the city of eternal spring and it averages about 24C year round. Yes, it's tropical on the coast but whilst it may be where drugs are shipped they aren't grown there.
Mexican adobe isn't especially appropriate. From what I've seen, narco bosses favoured new built and glitzy for their fincas. It was about showing off and displaying their power. Escobar's Hacienda Napoles famously featured a bull ring, a zoo with hippos, a shed chock full of vintage cars and a dinosaur park with gigantic ferro-concrete dinosaurs.
If you are looking at more humble dwellings then the building material of choice across the region is the terracotta brick, which is essentially a clay breeze block, hollow in the centre. The hillside barrios in places like Medellin are a sea of them, usually tin roofed.
If you want suitable planes then Italeri recently came out with a 1/48 Cessna and Testor's do a Learjet in the same scale. Both can be picked up for around ten to fifteen quid.