Hello Intel Design! Welcome to CRT.
There have been many good repliess here already. Depending upon your price point (and don't forget to add 16.5% hotel taxes to any price you're quoted), there are a number of options, although none have the "fun atmosphere" of a Sportsmen's Lodge or Hotel del Rey.
Just to make it clear when discussing hotel options:
The following hotels are all north of the Hotel Del Rey/ Key Largo/Monkey Bar/New York Bar enclave by around 5-9 blocks, depending:
Hotel Clarion Amon Plaza
Hotel Inca Real
Hotel Dunn Inn
Hotel Little Havana (formerly Zona Blue)
Hotel Castillo
Hotel la Amistad
Hotel Vesuvio (an inexpenssive new CRT sponsor)
Sportsmen's Lodge
Casa Vino - the small suite on the ground floor is fairly inexpensive, but this is an apartment, not a hotel).
Figure a taxi ride will cost less than $2.00 to/from "Ground Zero" Of the above, the Castillo meets your criteria of price and convivial, if not lively atmosphere.
You have the Morazan or del Rey options of course, as well as the Presidente; of these three, only the Costa Rica Casino Hotel Morazan would be considered a "mid priced" hotel for C.R.
Not to forget: Many guys absolutely love Hotel Freebird. Good CRT discount, particularly if you get one of the regular rooms with shared bath. The suites are reportedly very nice, and Dennis the owner is said to be a great guy. Four blocks south of the Hotel del Rey/Blue Marlin etc. Very close to Bar Idem, Pantera Rosa nightclub, La Mansion and other massage parlors.
All hotels above have security boxes in the rooms for stashing your valuables.
Whichever hotel you choose, be sure to stop by the Sportsmen's Lodge or the HDR and meet up with CRT brothers.
Why not go and post a Roll Call notice, maybe get in contact with other CRT guys who will be in town at the same time you are?
Have a fantastic trip...and be sure to post a trip report when you come home.

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