Moving by a mix of public transports and contracted lifts are an option too.
Not complicated.
Michel
I think that Izapa sounds interesting but it appears to be many hours from Chetumal. We have already seen many of the ruins near Xpujil so this time we want to see the ruins near Chetumal. Thanks.
OaxacaCat,
My appologies for that. Perhaps my mild dyslexia causes me to sometimes think Tapachula when I read Chetumal.
The ancient site of Kohunliche is one of the best in the area and is also one of the closest to Chetumal (about 45km to the west). I dont know if you would have included this ruin when you visited those in the Xpujil area. On the other side of the highway (north) a few kilometers away, is the site of Dzibanche, also well worth a visit and can be combined with a trip to Kohunliche. Not far from Dzibanche is the site of Kinichna, with a single structure uncovered and restored. I reached Kohunliche from Xpujil, when I was staying there and seeing many ruins over a period of days, by taking a private taxi to the site. With the hotel budget you mentioned, I suspect that you would also find a private taxi to Kohunliche from Chetumal to be attractive. Kohunliche has some impressive structures and equally impressive 3 meter high stucco masks of the sun god. The setting among palm trees is also quite nice.
The ancient site of Chacchoben is to the north of Chetumal, also about 45km away. This is also an enjoyable site to visit, and though it can be reached via pubklic transport, you might rather use a private taxi. If you were to only see one of these four sites, I would make it Kohunliche.
You can find information and images for these sites online.
I expect that you will find Portugal is a good place to travel with children. Public transportation is generally quite good, and taxis and Uber work well in the Lisbon area. August is the peak travel season in Portugal, so we will want to line up accommodations now. I can recommend the LP guide as well as Rick Steve's guide book.
In my experience, Cascais is a better place to stay with children than central Lisbon. There is a good commuter train that runs between central Lisbon and Cascais every 20 minutes. Cascais is a bit quieter than central Lisbon, and there are several good, small beaches right in the city. There are also several kid-friendly parks in Cascais.
Cabo da Roca is an impressive rocky head land jutting into the sea. There are many other places like it around the world, and unless you have never seen rocky cliffs and the sea, I would not bother. Sintra is beautiful, but will be crowded in August. Your child might like the gardens at Regaleira. The Lisbon Zoo is child friendly.
I would start with the Osa and end on the Caribbean coast. The Osa will get rainier as you get closer to September and the Caribbean coast will get drier.
If you arrive late stay in Alajuela. It is the city closest to the airport. There is nothing wrong with San Jose. There are just so many more interesting places. I would not spend time in Alajuela or San Jose. I would go straight to your first destination (the next morning if you arrive late).
You say Corcovado. That is a National Park in the Osa and you can only visit the park with a guide or on a guided tour. So how did you want to go to Corcovado? You can do a three day guided trek to the Sirena ranger station (not cheap). You would book the trek at a travel agency in Puerto Jimenez. Or you can go to Drake Bay and get to Sirena by boat (a day trip is much cheaper than staying overnight but overnight would be better). I like Drake Bay but I like the Puerto Jimenez area even more. If the three day trek is too much hiking or money you can also enjoy the rainforest and see wildlife without going to Corcovado. Check out Dos Brazos de Rio Tigre (rainforest hostel Bolita has an amazing setting and trails) and Cabo Matapalo. You have to decide about Corcovado and about where you would go (Puerto Jimenez area or Drake Bay). I would not go to the Osa for two days. You will want more time there (even if you don't do the trek).
Three days for the southern Caribbean coast is nice but you could add a day there as well. I like to stay south of Puerto Viejo (we like Manzanillo and Punta Uva but if you like nightlife you will want to be closer to Puerto Viejo) and in Cahuita as well because it is a nice town and the National Park is amazing. Or pick one and make a day trip to the other.
If you go from Cahuita to Tortuguero with public transport you have to change buses several times to get to La Pavona and then take a public boat (that is what we did) or you go to Moin for the boat to Tortuguero but that is more expensive ($35 pp).
I don't know if I would go all the way to Monteverde for just one day. I like the cloud forest but it is all about the vegetation. There is lots of wildlife but it is very hard to spot. You would see lots of hummingbirds and hopefully a quetzal.
I have only been to Nicoya briefly. I liked it but I will let others comment.
Manuel Antonio is touristy. I think you can skip it because you are going to the Cahuita National Park, Tortuguero and the Osa.
I don't know about renting a car for the last part. We got around by public transport. You can take buses to the Osa (if you choose Drake Bay bus and boat). But lots of people fly there as it saves time.
I would do this:
8 august - you will be very close to Alajuela so if it is late, stay there and otherwise go to San Jose
9 august - bus to Puerto Jimenez or bus to Palmar Norte, taxi/bus to Sierpe and boat to Drake Bay
10-15 august - I would choose Puerto Jimenez, the three day trek to Sirena and/or Dos Brazos and Cabo Matapalo
16-18: San Gerardo de Dota area (also cloud forest so an alternative to Monteverde)
19: back to San Jose and get to Sarapiqui
20-21: Sarapiqui (rainforest, wildlife, lots of birds)
22-23: Tortuguero
24-25: Cahuita
26-28: Beaches south of Puerto Viejo
Having two extra days is great so you have some flexibility and if you really like a place you can stay longer. If you can afford it, you could also go rafting on the Rio Pacuare your last day with pick-up in Puerto Viejo and drop-off in San Jose.