If you’re on a budget, which is understandable cash is pretty tight these days, there are a few things to consider. You really need the best bang for your buck, so always keep that in mind. I see a couple different types of light being used; fluorescent, CFL, and LED presumably in the back. I would stick to one type of light. Right now, LED light bulbs have come down quite a bit in cost. Whether you invest in a grow light, or have to rely on what you have available at your local hardware store, they are all incredibly affordable. If you go with the screw in bulb option, I recommend rigging up or building some kind of fixture like @skgrower mentioned. But with the amount of materials needed, time, and effort you might be better off purchasing a grow light. @Familyman420 mentioned a few, none of which I have experience or knowledge of. I personally use a Viparspectra reflector series light in my grow tent, and Viparspectra offers quite a few different sizes for all types of budgets. I got mine off of Amazon, and Amazon also has a litney of different off brand and imported lights along with the better quality ones. Mine is an import, but I’d like to think of it as a midgrade import. It’s not the top tier, not the junk, but it definitely gets the job done. But if budget is an issue, get LED “daylight” screw in bulbs like you would put in your lamp at home and use those. I am sure you can get a pack of 4 for like 15 dollars depending on where you are. Being that you mentioned one of them is going into flower, try and find lights with more of a red hue, the CFL soft white will do just fine. It has more of a yellow tint to it, which plants in flower love. Plants in veg need more whites and blues, plants in flower need more reds and violets. In the future, I recommend taking the grow course ILGM offers, it will be incredibly useful to you in the future I think.