We are planning on leaving from SJO,
Heading to Arnel for 2 nights and days, then Monteverde for a night and day.
Heading to Nicoya Pen for 3 days. Right now debating between Montezuma/Mal Pais/Santa Teresa area or Tamarindo area.

Then from there to Manueal Antonio for 2 days and nights
then back to SJO.

Thanks for tips!

Definitely rent a car. In my opinion you are still missing out on what there is to see and do in some great areas and choosing being on the road too much instead...

Based on no traffic issues and no stops along the way:
Alejuela to Arenal - 3 hrs
Arenal to Monteverse - 3 hrs
Monteverde to Montezuma - 5 hrs
Montezuma to Manuel Antonio - 6 hrs
Manuel Antonio to Alejuela - 3.5 hour

So almost 3 work days worth of driving during a 10 night trip in addition to eating up valuable daylight hours to do anything active since it gets dark between 5:30-6:00 all year round.

THANKS!! We are still working on the agenda but that helps a lot!

Do you think if we taxi, boat or horseback ride it will take off the travel times?

I saw a taxi, horseback, boat, bus trip that is for 5-6 hours that takes you from your hotel around Arnel to MV.

I would choose the taxi, boat, horseback because because it will probably be more fun for you than driving, but not less time. Also, make sure to use a reputable company for that trip -- one that treats their horses well.

Edith, are you really going to Monteverde for just one night? That is just not worth the time and trouble it takes to get there. The road is very long, bumpy, and unpaved. We used the Jeep Boat Jeep with Desafio - about 3 hours from Arenal. I would take a serious look at what you want to see and do in each place and rethink moving around so much. Hip is totally right - to me, that is just way too much moving around.

always rent a cheap 2WD save a lot from www.mapache.com

Works great...

You'll need 4 wheel drive on some of these roads, particularly around Monteverde and on the southern Nicoya Peninsula.

For sure, I'd limit my trip to ONE beach location and for sure, I'd NOT do Monteverde for just one night.

Or drop Monteverde in favor of 2 beach locations. 10 nights=3 locations (or less) ideally.