If you like to drink alcohol on the odd occasion or if you just happen to have some bottles hanging around, use those for weights instead of buying weights.. doing bicep curls etc. They’re usually only a few kgs maximum… or if you have a carton/slab hanging around, use that - preferrably not with the same techniques. Same thing goes for water bottles. You don’t have to drink to have a useful weight hanging around! Fill up some waterbottles and use those! If you’re not getting much resistance, try tying some together or use 2L bottles or start up a coin collection! I have one that’s 11kg … I’m not kidding - it’s a pain to pick up lol. AND I know I have money in there lol… unfortunately repetitiously picking it up won’t increase the wealth lol… but at least you’re getting exercise

If you have a baby or toddler, why not use them? There are many muscle-building activities you can do with your kids! Even just carrying them around and rolling on the ground flipping them over your knee (I can’t really explain that one any better without a demonstration, unfortunately but I know it works muscles lol) …… safest to try on a big bed or mattress lol.