I've been snowbirding the last few years for 1-4 months per year. Here are some things that have worked for me:
* I have a van that I converted myself (added a bed, refrigerator, lithium battery, camping cooking gear, spent about $1400 upgrades and gear). With this I can both free camp, some places in Arizona and California are warm enough most nights without heat. I love to camp at a place where I pay $450/month for camping and they have excellent facilities (bathrooms, showers, pools, hot tubs, gym, etc) and loads of activities... easily could camp there for months. Other people in small vans set up an additional tent or shade to have more living space.
* pick a non-traditional place like Tucson - I worked remote from there and paid $800/month in the winter 2020-21. However, that area is getting hot and prices have gone up alot.
* Someone mentioned Mexico, I went down to Baja for a month this year. I shared gas and acommodation costs (camped half the time and motel/airbnb in cities) with one travel companion, ate out 1 meal per day, other meals were from grocery, and did a few day tours. Our total cost per person was $45/day. There are lots of cities in Mexico with many expats.
*Other international destination - southern asia wouldn't be bad in winter.