How would you make a retractable fence for small dogs?

They may have something that would work for you.

https://guardianpoolfence.com/

I take a roll of chicken wire roll it out to 2 feet over the length I want. Fold each end back 1foot and use plastic tys to secure the wire to make a loop at each end. I put some lengths of 3/4" pipe 4feet long in the ground and slip the loops onto the pipe. I found that 1" chicken wire 3 feet wide worked for me. My dogs are small. They don't like the feel of the wire on their paws. If you have a long section you may need additional supports. Make sure you can pull the pipes out of the ground when you want to roll up your fence.

Check out all the web sites like Drs. Foster and Smith, Chewy.com, PetSmart, etc. There are many enclosures that you would be able to remove easily for lawn care day. Other than that, you could check into the fencing that home improvement store stores have that you can purchase all the segments and even a gate for it. They are mostly either plastic or lightweight slimmer wrought iron like pieces that are at least three or four feet in length and connect together. I have a garden on one side of my front porch that goes to the end of the house and in the spring before my Hostas come up and are noticeable and in the fall and early winter I had problems with the mail persons walking across the garden. I got one of the lightweight wrought iron ones to put over the edge of the porch and have had not problem since. You just want to make sure your fur babies can't get between the posts. The have connectors on each piece and most also have posts that push into the ground.

How about 25' retractable driveway guards watcg video this would work well https://www.amazon.com/Kidkusion-Retractable-Driveway-Guard-Black/dp/B00313J4A0/ref=asc_df_B00313J4A0/?tag=hyprod-20&linkCode=df0&hvadid=198090943423&hvpos=1o4&hvnetw=g&hvrand=17474142315728072943&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030040&hvtargid=pla-394069408318&psc=1 you would need to add maybe some tent stakes to keep the fence connected to ground between posts you could pull them up when you need to close/roll up fence for lawn service day.12-12" stakes you could tie onto fencing https://www.amazon.com/BareFour-Camping-12-Inch-Unbreakable-Inflexible/dp/B07HVYBT9S/ref=pd_sbs_468_5/143-4508356-8034441?_encoding=UTF8&pd_rd_i=B0797W1GD1&pd_rd_r=795011c5-3a3c-11e9-b485-5ba568500836&pd_rd_w=EaYb6&pd_rd_wg=vRoDm&pf_rd_p=588939de-d3f8-42f1-a3d8-d556eae5797d&pf_rd_r=ZDP4ARQF053KZQ56E6JF&refRID=ZDP4ARQF053KZQ56E6JF&th=1