Last year I scourged my cupboards of grain moths, only to go away for a few weeks and come home to find that they had started exploring the non-edible items which were all that I left stored in that cupboard. I tossed and screened a bunch of stuff again, and removed the contact paper from the shelves. After that I vacuumed up all I could find, washed everything, and kept grains out of there all winter. But they (the grains) are overrunning my kitchen and I need to keep stuff in that pantry!
It seems unwise to assume something similar won't happen again; should I re-contact paper the shelving? Contact paper is so gross and hard to clean—is it necessary to keep my brand new pantry interior clean from dust in addition to pests? I stored cereal in my freezer in my first real apartment, but I've graduated to such an elaborate variety of flours, and I can't afford glass containers.
As you've learned the hard way grain moths—also called pantry moths or Indianmeal moths—are tenacious creatures. So you're right to worry that they may return. I wish I could tell you otherwise, but that's the God's honest truth.
There are, however, some things you can do to help keep them at bay which leads me right into the first thing you should know about when dealing with bug infestations: bay leaves, bugs hate 'em. And not just pantry moths; bay leaves will also repel flies, ants and roaches among others. So that's sort of handy to know about! Another group of things that bugs of assorted provenance dislike intensely are essential oils like eucalyptus, tea tree, citronella and peppermint. I'm keen on these two solutions because they're harmless to us human folk, which means that you won't be putting anything toxic (to us) near your food supply.
But before you get into repelling these foul winged creatures, you will need to execute a pantry purge and cleaning. The first step is to throw away any infested foodstuffs, and then immediately remove the trash bag containing these items from the home. If you suspect that something might be infested but you really cannot bring yourself to toss it out, put it in the freezer for a few days, which will kill off any lurking pests. But: there will be dead pests in your flour? I dunno. This whole topic is just the worst, isn't it?
Once everything is out of the pantry, thoroughly clean the cabinet interior with hot, soapy water. Then wet a clean rag with white vinegar and give wipe the interior out with that. (If using bleach will make you feel better from a psychological standpoint go for it, providing that it's safe to use on the type of cabinets you have.) While you're cleaning, keep an eye out for any bugs and larvae that may be lingering. Also, I would not re-contact paper those shelves and here's why: the larvae can get under the contact paper and hide out from you. Like I said, this is totally the worst topic.
Once you've cleaned everything out, go ahead and apply some of the essential oil and/or place some sachets of bay leaves in the cabinets. Since this has been a persistent problem for you, I would strongly suggest you get a set of Cupboard Moth Traps.
As for storage: glass or metal canisters are pretty crucial for storing your grains because pantry moths can chew through plastic. Double bags won't stop them. I know you said cost was an issue, so may I suggest getting a set of The Jars Of My People? A case of 12 in the 32 oz. size will run you around $20. You can, of course, recycle old pasta sauce jars and such but be aware that the seal on those jars might not be solid enough to keep those moths out. They are incredibly wily little bastards.
My best friend is planning to stay with me for a weekend for a wedding in my city. However, he called me up this morning and told me that he thinks he has bedbugs: His parents had them a few years ago and thought that they got rid of them, but recently visited him and left one of their suitcases, and since then, he's woken up with what look like bedbug bites a couple times. He's taking it in stride, no big deal, just cleaning and vacuuming thoroughly, since in his mind that got rid of his parents bed bugs pretty well. To my mind, they thought they got rid of them, but a couple years later gave them to him, so obviously they didn't.
Anyway, this is less of a pest-control question than it is an etiquette question. I obviously do not want bedbugs, am recovering from some arm injuries that make cleaning well really difficult, and the same injuries have made me broke. I don't have the financial, emotional, physical resources to deal with an infestation. What do I do with my friend?
Hoo boy. I'm going to break two rules of mine today! For reasons I've spent way way way too much time considering, I don't field cleaning etiquette questions because giving advice on situations such as … oh say … one in which one housemate does an unfair share of the housework is impossible for me to do in a general enough way to be truly helpful. And here's why—the approach you take to these kinds of situations necessarily has to account for the personality of and relationship you have to the other party. There are just so many variables in play with these things, ya know?
The other rule is that I run screaming from anything on bedbugs because AHHHHHHHHHHHH HOLY MARY, MOTHER OF GOD NOT BEDBUGS ANYTHING BUT BEDBUGS [DIES].
But in your case, I actually think what you're looking for here is permission to rescind the invitation to your friend to stay in your home. And so I'm giving you that permission. Sometimes in life we just need someone else to tell us it's okay to do things that we maybe feel a little weird about. Hugsssss.
You've given me enough information here that I feel comfortable suggesting the following approach in terms of handling an awkward spot with your bestie, but of course you should adjust this advice to best suit the relationship you two have. First of all, a phone call is probably in order. Texting, email, telegram services … they all suffer from a lack of tone that can cause misunderstandings or hurt feelings. So get on the telephone and tell your friend what you've told me: that you are broke and still recovering from a serious injury, and that the risk of acquiring the dreaded bedbugs is one you simply cannot take right now, physically and financially. Acknowledge that you are leaving him in the lurch, justified though you are in doing so, and come prepared with some alternate lodging suggestions (local hostels, inexpensive motels). While it's not obligatory for you to do so, that small amount of research will hopefully go a long way in making him feel less put out by being put out. I know you said money is very tight right now, but if you can at all swing it maybe offer to buy him a drink while he's in town. Again, that's not required but it is a nice gesture.
Since we're loosely on the subject of bedbugs, here are a few online resources to help you if you suspect or have confirmed you've got an infestation on your hands.
Bed Bug Infestation | WebMD
How I Fought Bedbugs And Won | The Awl
A Ten-Step Support Group For Bedbugs | Jezebel