No one likes to be that person who feels like they are being left behind and lacking something in their worship because they struggle with poverty. That you can’t go and buy icons and extravagant, or even comparatively decent, offerings. As someone who has spent considerable time in that situation here are some tips.
1. Make your own icon. Find a recipe for salt dough clay. Paper-mache it. Get air dry clay. If you have access to a printer, print a picture you like. Be creative. Shoot get a bowl and fill it with sacred symbols you have for said deity.
2. Offering bowls can be kitchen bowls, or anything. It can be grandmas chipped teacup you inherited. They dont have to be replica vessels you have not a prayer to afford yet.
3. Olive oil lamps are most cost efficient than candles. Make the switch. An easy lamp can be made from a heavy mason jar with a hole cut in the lid for a wick.
4. Swallow your pride and earnestly offer what you have. A portion of your meal. A spoon of cornmeal. Rice. Use staples in your house. Bread is a perfect one we take for granted. A tablespoon of honey in water can make a libation in a pinch. Or maybe a spoonful of tea or coffee.
5. Experiment with burning different herbs you have for incense.
6. Performance such as dance, song, athletics etc are all time attested simple offerings. Poetry is good.
7. Realistically while we would love to grace worship areas with flowers, it is often not possible financially. Invest in silk ones so you can save pennies for real flowers on special festival days/occassions. Silk flowers can easily be perfumed.
Beloved in Light 
You can collect wild flowers too. Even in cities you can find them if you invest the time. Also you can dedicate tasks to the deity, especially if they are connected to the domain of the god/goddess. Like weaving for Athena or cleaning for Apollon.
Absolutely! Unfortunately up here there is only like an average 3 month window for that so I cant do it much, but I have and is definitely helpful.
When money is tight, I buy a large 1.5 L bottle of cheap wine (like $9-12 in my area) and throughout the month I prepare a half wine/half water mixture before I make my offerings and use that. I figure the Greeks cut their wine with water, so I can too. I do try to do just wine on festival days, important offerings, or daily when I can afford it… but that isn’t always.